If you look close at the canopy, there is a faint line molded into it...that's where you want to cut it. It will fit down over the sides of the cockpit area, probably about 1/4". As far as the rear goes, it will have open areas between the stringers unless you fill that area in with small balsa blocks, then sand them to contour the area round, if it isn't covered yet. The open areas will do no harm, just make sure you keep it clean! This pic is not a Four Star, but you will get the idea as for what I'm talking about! I'd also recommend a good canopy glue, like Formula 560 by Pacer! It's quite thin, but only a very small bead around the edge is needed. Use masking tape to hold everything down tight and let it set up for at least a day before you remove the tape...it may take up to a week to dry completely clear, but it will be glued to the covering crazy good!