I've only done one but the gal wanted them all the same size so I picked the biggest logo, cut it out with a decent space on all edges (centered) then made a paper template, I laid the paper (see thru) over all the other shirts to mark my cutting lines. some had more shirt around the logo and some had less but the pieces were all the same size, then added sashing, it was exactly like she wanted it. BTW, I only used interfacing on two that were very thin, the rest of them I did not and it was fine, just don't stretch. good luck