Help with measuring for woolies

[Hellux]

I need to get some longies on fsot and don't know how to measure dd correctly... Should the tape be loose or pretty snug? With fitted on or off? And how do I measure rise?

Should the pants correspond to those measurements pretty exactly, or could they be a little bigger (or smaller)?

[kbevie]

With diaper on. Pull snugly (since wool stretches a little). Rise is the diaper from belly button, under crotch, up to top back.

[Hellux]

Great, thanks!