OK - Once you have done it you will say easy-peasy!!
Firstly, as QTpie said - check with your airline for the luggage policy. They vary wildly - check your KG, your LO's KG's and then what extra 'items' you are allowed. I expect you to have no problem with the buggy at least. I understand you wanting to take your car seat to Mexico so think you should pay for it if you can't take it for free. Take bags that are not too heavy and easy to get off the carousel (and that you can spot quickly). I would wrap your car seat and in my opinion you should carefully pack and check in your buggy. I have an expensive one that I can't be without as Ollie sleeps well in it and when you are out all day visiting friends and relatives you need somewhere that is known to your baby. I have heard too many stories where the buggy gets damaged and although it can be mended and paid for by the airline - it was worth more than that to me.
Also, don't overdo what you take in your hold luggage - if it's hot - don't take more than one or two jumpers, trousers etc. Relatives are always happy to wash and iron (makes them feel useful!) Use the same as you would do. Lay it all out and remove 50%!!
Hand luggage - Keep it to a minimum if you are by yourself. I took two bags and a hand bag in one direction and cursed myself! Since you are only doing a single flight, just one easily carriable bag (I used a small 'gym' size rucksack for a 2 leg journey, plus my handbag.) I took - extra vest and babygro (I travelled Ollie in a long sleeved vest and babygro as I felt it would be more comfortable than clothes. He didn't need a jumper or blanket at any time once we had arrived at LHR. This combination also meant that it was cool enough on arrival in 21 deg. Sydney), lots of muslins (used as feeding bibs and mopping but I have a sicky baby), just a couple of basic toys and his taggi comforter. He preferred the remote control, seat belt and TV anyway and I also gave him the plastic cups, bottles etc to play with and he loved them. Clean underwear for me but then I was able to shower during my short stop - you may not need this (unless for emergencies). I made do with no clothes changes for me and had to make do with a top that had been sick on but I don't regret this! I took basic supplies of Calpol sachets, moisturiser for me, lip balm. I didn't need books or magazines. Put flight docs, passports, visas etc in one wallet and be fastidious about putting them back to avoid pulling bags apart to find things. I also wore 'combat' style trousers with pockets so I could slip the passports and boarding passes into a leg pocket if needed. I carried 7 nappies for a (door to door) 27 hour journey and only used 5. Add a large pack of wet wipes as well. Oh and headache tablets! (Food and drink, see below)
Unless you have lounge access I would recommend a small flat (cot) sheet to put on the floor in the airports to put LO down on when you are waiting.
Food and Drink - if you are BF then wear an appropriate top to allow nursing for a long time if required. If FF or combi (as I am) then I would use cartons and sterilised bottles when you fly. Allow a little extra for on board delays. Now, at LHR I was asked to taste 50% of my stash of food, milk and water. They didn't mind which so I would suggest filling your bottles with water and then tipping out once through security and also be prepared to ditch opened cartons if necessary. I only had to open one carton which I then tipped into a bottle and used straight away as I had some extra water that I could taste instead. If you let me know closer to the time what you are taking and what you expect to use I can tell you what you will need to taste. I am guessing you will be on early weaning of your 6 month. Even if BLW I would use a jar (just simple veggies) if you can. For my long journey and even at 8 months I decided to up the amount of milk rather than shovelling in lots of hard to digest food. Ollie only ate very small amounts and almost nothing on the actual flight. At 6 months, if your LO doesn't take any food it won't be an issue. I didn't know I was going to do this until we flew but it worked for us. The pressure plays havoc on their tummies with lots of gas and unexpected poos so it just felt like the kindest thing to do.
You will get no end of people who are willing to hold your LO. Hopefully this won't be a problem. Luckily, Ollie will go to anyone and is very, very smiley which meant everyone wanted a hold - from the young guy at the x ray machine, to the stewards, to fellow passengers. I had no end of other help as well - there is always someone willing to pull your suitcases off the carousel, pushing your trolley etc - just let it happen! In LHR I was able to jump the immigration queue as I was on my own - be obvious at those times! The hardest time for me was trying to eat my food on the plane. Either someone else held him or I sat him oln my lap and gave him s tiny bit of my bread roll or lettuce to eat whilst I shovelled. Ask for your food to be kept for you if necessary. Make sure you eat and drink plenty as it is stressful and dehydration will not help.
I flew Qantas and could only request a Bassinet but I called a week before I flew and they were able to confirm it. I also asked for a particular one which worked well as it was the one closest to the exit doors which meant I could get off the plane quickly which worked for me. It makes sense to look at seatguru and see where you are so you can know and not be hunting for your seat. You will get extra leg room which is great. Ollie hated the Bassinet but a other babies slept well in theirs - you may know what yours is likely to do even now! I ended up nursing Ollie for much of the flight and I actually enjoyed having the long cuddle. I ignored routine - he slept and ate when we felt like it. Ollie is a poor sleeper normally and there was just so much going on. I decided not to stress and just went with the flow. He was horribly tired but there wasn't much I could do which didn't involve tears. The baby we sat next to slept much of the journey in the bassinet so it's each to their own. Your baby (probably) won't be allowed to sit/play/sleep on the floor so don't expect that.
I also booked a pushchair in the airports and also meet and assist but neither worked very well for me. We only had a pushchair in Sydney - they didn't do for either the stopover or at LHR so ask for this but don't expect it. I also ask for Meet and Assist but it was patchy and tbh it was pointless as I got it when I didn't need it and when I could have done with it there was noone in sight! If you can ask for this then alert the stewards on the flight so they can call ahead and request it then as well.
Oh and going to the toilet was surprisingly easy! Either get someone to hold your LO or if he is sitting then take him into the one with the change table which was just a flat top that you flipped down above the toilet. I was able to go to the toilet underneath the change table with Ollie sitting on top! He loved looking into the mirrors and had fits of giggles whenever I turned the tap on!
I didn't take a sling but that's because Ollie has grown out of his bjorn (plus I hate it) and I didn't want to buy an expensive one just for the journey. I have to say that as he sits well anyway and there was no end of holders for him it wasn't an issue but this should be your personal choice.
Overall, it was tough but also easy if you get my drift. It's not something I want to do every week - but even without a baby you wouldn't want to but it was much easier than I thought it would be. Just go with the flow and be super organised.
Sorry, its a HUGE essay - probably as I have been back only 2 days so it's very fresh in my mind. Ask any more questions at any time and I will be happy to answer.
Lastly, jet lag! For us, we landed in the morning at LHR and so had the day naps to acclimatise so he slept well in the UK with no hint of jet lag. Coming back here is tough - we landed in the evening and have 3 very tough nights with Ollie being awake for a couple of hours each night and lots of wake ups in between. Since you are travelling the opposite way I suspect your jet lag will be in the UK instead.
Good luck - when are you going?
XX
