I answered you on youtube but in case you didn’t see my response, here it is: the two measurements I would take would be the length and width of the kid’s torso and compare it to the existing pattern. If you take a look at our pattern, you’ll see that main pieces are in quarters. Let’s say you want to increase 1″ in length and 1″ in width. I’ll take the front pattern for my example. So on the side that has “3” on it, I’ll increase that side by 1″, that gives me a longer length. Then I would tape the extended 3 side to the matching 3 part of the pattern. Now on the side that says “2”, I’ll extend this full side by 1/2″. Front pattern is done. Repeat the process with the back pattern and now you have a pattern that’s longer by an inch and wider by an inch. If you’re doing a big increase, you may want to consider take the existing pattern and enlarging it on your printer just to experiment with it faster. Just use cheap fabric to test your prototype. Hope this helps.