QUOTE
What size brush or pen or something to colour the panel lines? And what paint colour code/recommended brand?
Also how to remove/hide the discoloured areas where the parts were joined to a frame?
Sorry about the terms, I don't know what those are called.
For beginners, I suggest that you start with some simple Bandai Gundam markers to do the panel lines, use the oil based pens, those come out nicely. Black, is ok, grey is better for more realism.
To hide the discoloured areas, buy some sandpaper in various grades, 400, 800, 1000. Start with the roughest grade and sand down the affected part. Then progress to the finest sandpaper and soon the mark will dissapear. You can do a wet sanding technique, this will help your progress.
If you really want to do a good job modelling, you should visit some local malaysian modelling sites, try the Malaysian Scale models tips and hints section go to the link below
http://z12.invisionfree.com/ScaleModelsMal...php?showforum=4