I lay the fiberglass on the boat and brush it out with my hand. Where it has wrinkles or buckles I brush on the bias. This helps to lay the fiberglass flat. At each end the cloth may not follow the contours well enough. In this case I cut it, sometimes overlap the ends...sometimes not. I will later put more layers of bias cut cloth over the stems anyway. I then cut off all that's hanging down...except for 1 or 2 inches. I brush it out with my hand again. At this point it will by laying nice and flat with no wrinkles. All that remains is to wet out the cloth...which I do with fairly good quality brushes. Other people have their own favorite way. So...the answer to your question is...yes...you will have a sense of fit and draping while the glass is dry...and it will be ready to wet out. If you have some concave surfaces that will make it a little harder, but you still do it nearly the same way. If a wrinkle developes while applying the epoxy simply brush, or work, on the bias until the wrinkle is worked out. Now...what happens if I end up with a wrinkle I can't work out? This has happened...but not often. I simply cut the damn thing and overlap it, later feather it....and add a patch if necessary. The simple fact is...the boat doesn't have to be perfect...it has to LOOK perfect...or as close as we can get it. God...I feel so dirty now from having said that....