When to start my period

Okay, so I know this is going to be a crazy question and I should probably know but I was never really TTC. So I have spotting before my period and then it stops for a day and then my flood gates really open. However I do not know if I should track my period from when the spotting happens or when it’s in full swing.

When I say spotting it’s clear when I wipe that I see it. It’s not speckles but blood. Might be a little crass to explain it that way but I want to give more info to make sure I get correct answer. I’ve looked online and I keep seeing mixed things about it.

Any info will greatly help!