Just because the guitar has six strings doesn't mean you have to constantly go looking for six-note chords,
especially if you are playing in a combo of some sort. Remember, barre chords use repeat notes to make up
the full six strings. Sometimes its better to use bits and pieces of a chord than the full version. It's easier to insert as a part, and more compact-sounding in a band situation.
Which bits and pieces? The best way to approach it is to ask yourself "what is the essence of the chord?"
- If it's a simple major chord, include the major 3rd to establish its major quality. The major 3rd and the 5th, or the major 3rd and the root will do that for you. Go looking for all the places you can find these two-string chunks.
- If it's a minor chord, same thing. The minor 3rd is the note that says "minor". Add to it the 5th or the root. If you've located the majors, you've also located the minors. Simply flat the major 3rd for a minor 3rd.
- The root and the 5th played together will fit against either minor or major.
- If it's a 7th chord, include it in your double stop (another way of saying two notes played together). The major 3rd and the flatted 7th together will state the quality of any 7th chord. The flatted 7th and the 5th to a lesser extent, but it still works.
- Sus 4 chords obviously require the 4th, which replaces the 3rd. The root and the 5th are your only choices to add to it.
After a while you will find you can string melodies together using these bits and pieces, weaving through the chord changes. Remember that "the chord of the moment", as I call it, dictates the
rules. Never forget what key you're in and what the chord of the moment is.
Next, go looking for double stops that use notes two strings apart. Again, look at any old chord and select notes from it which are two strings apart, a "sixth" away from each other. By that I mean they are separated from each other by an interval of six scale notes. Build melody lines out them in the same way, by keeping track of each chord of the moment.
Practice by playing along with your favorite records, or better yet, with someone else. If necessary, write the chord changes down so you're always aware of the chord of the moment, which is the most important thing.
Keep practicing -- it can be worth it. I read The Eagles are doing a New Year's Eve gig to bring in the Millennium, for $10,000,000!!