Only small increase in girth while clamped

I am about 5 7/16” unclamped. During clamp, I am 5 9/16” girth. Is this normal? I’m using a shoe string instead of an actual clamp, because neither the medium or large clamps that I’ve found locally fit right. I seem to get a pretty good tightness with the shoestring. Maybe because I have no comparison, I’m not getting the right amount of tightness.

Do not use a shoe string. You need the pressure a bit more evenly distributed.

Did you gain any girth from the newbie routine?