I am also trying preseed this cycle!!! I used it last month but miscalculated my ovulation date so I'm not counting it that time lol

opks are very helpful I use the internet cheapies but they give VERY CLEAR results and I saved a ton of money using them, i think i only spent $31 on 25 ovulation tests plus 10 hpts!!! I find that sex from behind (doggy) is deeper and your parnter can shoot where its supposed to go

lol i use doggy because my DB doesnt shoot he kind of leaks out lol so if im doggy style gravity will take it course and the spermies will go where they need too and a MUST is always put ur legs up or put a pillow under your back to keep the spermies in (in my case i keep my butt in the air lol)...anyway i think you should go off your most recent cycle, and try to keep a record of your bbt and your opk results, it'll help you figure out a pattern with your cycles
as far as vitamins and methods....(where to begin...)...for a lack of better examle, these are things i have tried since i have been ttc for the past 6 months:
Preseed (trying this month)
softcups (trying this month) (I think you would really like this!!)
evening primrose oil
prenatal vitamins (always trying)
vitamin c vitamins
folic acid (always trying)
robitussin and/ or mucinex
grapefruit juice
pomegrante juice
pineapple core on days 1-5 dpo (trying this month, it helps with implantation)
increase your water intake to 64 oz a day
cut out ALL caffiene (coffee, soda, and YES tea!!)
SMEP (i think you will really like this method in combination with preseed!!!)
avoid ibprofen!!!
bbt chart
if you can reach it, examine your cervix with fingers to see if its open, closed, high, low, soft, or hard
relax!!!!!! (there has been alot of women who swear by this)
honey and cinnamon intake
I hope this helped you!!! good luck and baby
P.S. Im not saying that these things will work for everyone but lots of women swear by these remedies, and also I think that ttc is just a matter of finding out what works for you, and what doesnt...so venture out and try simple things, they might just make a difference...