Measuring: a dummies guide 

Quick background: I lost 100 pounds a couple of years back and want to stop using the scale -- which I use to make sure I don't gain the weight back -- as the normal weight fluctuations stress me out. 😳

I'm thinking of using a tape measure to track instead.

What do I measure for this? I do strength training primarily (thank you FB Strong & Mass), so I presume some increase in my biceps or glutes etc. could be normal and not alarming? Do I just measure my waist circumference? I guess one shouldn't see an increase there if you don't increase your body fat?  Is that correct? Am I just making this needlessly complicated? 🙃

What do you do or recommend?