I spend most of my time in my studio doing everything by myself – engineering, playing guitar, mixing. Ideally, an extra set of hands would really come in handy, especially when tracking a guitar part. I’d love an intern or a tape-op, but the reality is, it’s down to finding tricks and shortcuts for me.
For acoustic tracks that I don't want to record in the control room (due to noise or acoustics or whatever), I use an M-Audio sustain pedal (with a headphone extension cable attached) to send a MIDI note to Pro Tools, telling it to begin recording. That way, I can be ready to play the part, in the quiet of the living room, and not have to run back and forth, throwing headphones around and hoping I did not miss the downbeat.
For other tasks, more invention is needed. Mic'ing a guitar amp can be relatively straightforward, but finding the sweet spot takes some trial and error. You can spend your first 20 inspired passes just getting a tone. I found a way to eliminate the hassle of placing mics, playing a bit, listening back to it, moving the mic again, playing again, etc.
Once I get the right sound coming from my amp/pedals, I loop a musical phrase and then start adjusting the mics. My Line 6 M9 pedal has a 28 second looping function on it, as do many other looper/delay pedals. I simply play 28 seconds or so of the riff I’m going to record, with the attitude and tone I want for the track, and let it repeat as I move the mic(s) around to get the sound I am looking for. This gives me the sound of my guitar -and my hands - playing the right part, thereby eliminating many of the variables that make up your recorded tone.
Once you have the amp set up and the right part playing through it, you can experiment with close and far micing, different microphones, etc., all with a tireless session player gladly obliging you with a consistent source to experiment with.