I'm really fond of using the Basic Action Template from the Action 4 book of Gurps. But I recently realized that I don't use it as written in the book, because I mostly use it for quick NPCs. So this is the method I use:
- Pick a Set of Attributes
- Add the Basic BAT skill list
- A number of Packages (here's a handy index)
- A few rough adjustments of skills and advantages
And that's it! You now have a quick character with a fairly robust array of skills!