Hi!
I have been building and constructing model planes for 36 years and if you don't have a small band saw the best saw is a small Japanese wood working saw.
An X-Acto saw is no good!
I also recommend a wood working knife with expendable cut off blades and an X-Acto nr 11 knife.
A must is also a 25-30cm long aluminum U-beam for sanding and of course the best sandpaper available: The Portuguise made Indasa "Red line" Rhino dry sandpaper!
3M and Norton have nothing compared to this sandpaper !