We use the Talislanta 5E rules.
The gist of it is really simple:

1. Explain your intent to the GM.
2. Roll a D20.
3. Add revelvant skills or attributes.
4. Subtract difficulty or opposing skill.
5. Look up the result on the Action Table (printed on your character sheet).

Talislanta is available for free from The Talislanta Library where the creator, Stephan Michael Sechi, has put them up for anyone to use. I highly recommend all players download the PDF’s.
Relevant sections to read up on are the rules (naturally), the Western Lands, skills and quirks. Magic users are highly recommended to read up on magic, and particularly the modes they have available.

The character sheets we’ll use are created by your’s truly, and are an adaption of the 4E sheets. They can be downloaded here