Ovulation strips!?

So I just ordered some ovulation strips tests never have I done this ....I just ordered 20 of them, for now. when should I start testing?? Im on my period now I usually have 7 long days of period so im on my 5th today should I start testing right after period? I am also starting vitex pills this cycle wish me luck im trying this month everything why not lol been ttc for yearsss with nothing no pills or test and no baby yet so we'll see please anyone help with this test