Mummy's, how long did it take you to concieve using ovulation tests???

I have an almost 7 month old and I'm currently TTC baby #2

This is our 3rd month of REALLY trying and our 1st using opk's.

With our 1st bub, I used opk's and once I got a smiley face, we BD'd on that same day, twice the next day & once the day after that and ended up pregnant.

I know it may have just been pure luck, but I'm wondering if we have similar chances of concieving if we use opks and BD alot once we get a smiley face this month??

I also have irregular cycles (still get AF every month, but cycle length varies by a few days to roughly a week and a bit)

We'd really love 2 kids close in age, so any tips or advice would be much appreciated.