Having the proper tools will make your guitar-tech life a lot easier. Here’s a list of the most necessary tools. Of course you could get a professional guitar tech tool-kit if you do a lot of setup work, but regular tools like these will work just fine.
1.) Screwdrivers: Flathead, Philips head (and possibly a Torx depending on your guitar).
2.) Wrenches: Adjustable and socket
3.) Wire/cable cutters
4.) Allen Keys
5.) Steel Ruler
6.) Guitar Capo
7.) Polishing cloth and a clean rag
8.) Teak Oil, Tung Oil or Lemon Oil
9.) New Strings
10.) Tuner: Accurate boxtuner, or computer
11.) Guitar Cable
12.) Steel-wool, 0000 grit
13.) String Winder
14.) Guitar workbench, with neck support