Have you ever had a pair of infant or toddler pants that were just a little too loose? My first son is thin. When he was a toddler, his waist size in pants was smaller than his pant length. So I put a belt on him for a while. What a pain to take off every time he needed a diaper change. Then I discovered the adjustable waist pant. Hallelujah! But these can be hard to find in infant sizes (24 months and smaller). So he wore athletic pants for a long time! Good ole elastic pants!
My second son is.... not so thin. :) He is built like a tree trunk, round and solid! With the added bulk of a cloth diaper, now I run into the opposite problem. He needs larger pants in the waist, but they are still a little too loose.
My sister-in-law had the same problem with pants staying on her son too. She introduced me to the Dapper Snapper. It's an adjustable toddler belt that snaps in the back, so you never have to worry about taking it off during diaper changes. I thought it was a great invention! Created by a mom, of course! And they come in all different colors to either match an outfit or add flare.
I really didn't want to spend $10 per belt. So I made my own version of one. It's a simple concept. But I've never attached snaps before, and I went through almost a whole package before I figured out how to use the tools and attach them correctly. Typically I could make about 4 belts with one package of snaps (at $2.59 per package, plus my 40% off coupon because I'm cheap). I already had the black elastic on hand. But I did check the elastic out to see if I could get a navy for jeans and tan for khakis. Unfortunately I only found black and white elastic in my local craft stores. More colors are probably available online.
I didn't measure anything, which is strange for me... the perfectionist! I just placed the first outtie snap and then fitted them on the jeans to the tension I liked, and placed the rest of the snaps. I used a youtube video as a reference on how to attach snaps, and of course now I can't find it! The problem I had was putting the innie snaps on backwards, or hammering until the metal was crooked. I seriously had no idea how to attach these things! The innie piece with the side that feels raised up is the side that gets hammered against the prongs.