If the canopy has a frame which stands proud, you can do it a panel at a time using Tamiya tape. If you use a toothpick or similar to press the tape right into the edge, you can then use a sharp craft knife blade to cut against the frame - pressing in with the toothpick lets you see the edge you have to cut quite clearly. If the edges are not very pronounced, after you put the tape on you can rub over it with a pencil to show the lines & then cut on them.
If you are looking for Parafilm M, Flexible masking tape, Frisket film or Tamiya tape, we stock them all. Parafilm M is quite tricky to get used to, but ours come with full instructions.
Happy masking!