when to use ovulation tests?

M
I stopped my birth control pill at the beginning of 1/2017. I had been on it for 10 years and had 28 day cycles due to it. Since I got off, I have had a 34 day cycle and then a 53 day cycle. I have no idea what the next cycle will bring. 
I decided to buy a 50 count box of LH strips to find out when I ovulate. I am finishing up my period now. 
Any advice on when to start taking them? Also, should I take them daily or every other day until I see the line darken a bit? I don't want to miss it but would also like to not go through a box every cycle if possible. 
I read the directions and have looked for other threads, but had trouble finding an exact answer. 
Thanks in advance!