Aah.... i remember when i first started making model airplanes, the canopy.... ah yes.... SCREWED IT UP MOST EVERY TIME! i have learned over my time of model building
i use the normal testers glue in the red tube, i use only a little and make sure my hands are clean before installing the canopy, i apply glue on the aircraft where the canopy goes, not on the canopy, if you put the glue on the canopy, your are almost guaranteed to fail in canopy installation. and only use a little bit, too much will get all over the canopy. Also what i like to do is, make sure i know how to attach the canopy before hand, think of a game plan, make sure it has a smooth fit in the spot, if it does not make it fit smooth before installation, if it fits, or when it is made to fit well, then i apply the glue, and install the canopy, usually it works out well. one of my most sucessful canopies was on my P-51D mustang "Patriot",its almost perfect.
not a spot of glue on it
And like everyone ells says, free handing your canopies will always lead to disaster, i would place masking tape in the spots you do not want painted, and only apply the paint in light coats so it does not... seep through the tape, also as many have stated here, make it one of the last, if not the last installation of the aircraft, so you don,t have to work around it in fear of screwing it up, beacuse you probably will!
also its a good idea to make sure the surface you apply your canopy to does not have paint on it if your using glue... beacuse paint tends to soften up when glue is applied and could get on the canopy and ruin it.
sad part is for me, lol... these are all things i have learned the hard way! but Patience and practice makes perfection just like my P-51! hay thats a lot of Ps...