[CHAT] what do you use to mark your grid?

I’ve been cross stitching for 15 years and I feel like I am learning something new everyday in this subreddit. When I do a larger piece, I only mark my center and I just meticulously count based off completed stitches to figure out where I’m at. I keep seeing grid marks on folks aida and I’m curious as to what y’all use. Please sound off in the comments and help this elder millennial who never thought to take her cross stitch learning to the internet! ❤️