There's plenty of advice in the recording section regarding mixing guitars and bass. Try the search function, as there's a lot of info there.
Main thing is to;
1. set your drums up so they peak at -6db on your master fader.
2. Bring up the bass to a level your happy with.
3. Bring up the guitars and adjust them so you hear both the bass and the guitar.
4. Balance the guitars and bass with the drums again.
Have a coffee
5. Listen and decide what is missing, which sounds have been obscured? kick perhaps?
6. Use Low pass and high pass filters on your busses/tracks to restrict the frequency range of each instrument to allow clarity.
7. Using the Q on your EQ you can find the frequencies you need to adjust.
If you have to use a lot of EQ, probably consider changing the way you recorded for your next project. It's a massive topic, so that's enough for now. Good luck! oh, and monitors help a lot.