Never tested for ovulation! Suggestions please

[missi1717]

So I am ttc #2 on and off for almost a year. I've never used an opk before. Can anyone suggest a brand I should be using and what I should be looking for? We are trying to conceive a boy (we have a daughter together and my husbands daughter from a previous marriage).
So I've heard to only have sex on your actual ov day and not the days before (boy sperm faster swimmers, die quick/girl sperm slower but live longer)
Anyone who can point t me in the right direction, I would appreciate it! !!

 

[RoseArcana]

Are you UK or US?

If UK I use:
https://www.amazon.co.uk/gp/product/B001PPJVJK?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Cheap and cheerful!