I listen to mostly blues-rock, so the riffs I want to write are all based around bass/guitar/drum interplay. Unfortunately, I can't find a band, so I'm trying to write music that sounds good on its own. Essentially, I'm just trying to string together chords, seeing if I can include inversions somewhere, and trying to sing over it. Two problems

1) I'm not sure if riffs work unaccompanied
2) I have trouble finding a vocal melody most of the time
The great thing about the blues is, you can play it with just a guitar and it'll work, with some practise. Heres what you do, get an acoustic guitar, and play through a 12 bar blues. Play it through once, just to make sure all the chords or dyads or whatever your using are in the listeners ear. Now, on the second repeat of the progression, solo every second time you hit the chord.

ex. First Repeat : E - E - E - E - A - A - E - E - B - A - E - B
Second Repeat : E - small solo - E - small solo - A - Small solo - E - small solo - B - A - E - turnaround solo

Keep doing this, and once you get used to it you'll start to just know where the solos belong and where you should be playing the chords.
Quote by Zaphod_Beeblebr
Theory is descriptive, not prescriptive.

Quote by MiKe Hendryckz
theory states 1+1=2 sometimes in music 1+1=3.
Maybe I didn't explain myself very well :P

I was just wondering if there is any criteria for what works without a rhythm section - a lot of the time, when trying to write things, I imagine a drummer playing it to help me with the rhythm, but then I start imagining it with a full band, which won't be the case :/