Typically when you have a positive OPK, you will ovulate in the next 24-48 hours. So if you had a positive yesterday...I would most certainly do the deed! Good Luck!
I'd do it today too to cover your bases. The two times I got pregnant, we did it the day before positive opk (I was guessing but got lucky), the day of and a day or two after...there is a website called sperm meets egg and it's for people who've had miscarriages but it works for anyone. I think it's day of positive opk, day after, day after that, skip a day and then day after that. Something like that...