I tend to try and not repeat the line. My guitar rythms will have the same chord progression, say a C, G, C, Emin, Dmin, C... I will play it in that form twicw, and then work in a C, G, Amin, Dmin, Amin, Dmin, back to C... Another thing I have been doing is playing single note, or a 2 note backing solo on another track. It fills in the void of repetiveness, makes the song drag a little less. Try it out. If you have programmable drums, Make different temos at different points in the song. Say you have a song with a repetitive 105bpm background, about 1/2 way through the song, change it to a 85bpm, or higher, say 145 bpm. take the drums completely out for a 30 second period, and play a slow solo. there are all kinds of things you can do with electronic beats, on your recorder, brother. you just have to experiment with it.

I'd just let the last strum ring out. Then copy paste it in a new track in Audacity (or software of your choice), offset it to where it should be, then quickly fade out the excess ring of the previous repetition. Mix tracks, rinse and repeat. Works best if you have a clicktrack to use as reference for fine alignment.

I have done that on certain songs to fade into the bridge, or chorus, and then used that one chord to fade back into the next verse before. But here lately I'm like Alex, it's becoming less enticing for the song. It is harder to sing vocals sometimes. I have been having difficulty making my vocals not sound repetitive, over the top of the chord progression. I have been trying to write a simple lead over the top of the song to use as a reference point for the vocals. Kind of going the opposite of singing the lead, like a Pink Floyd type thing from "Wish You Were Here", but the opposite. Does that make sense? I often write melody first, though anyway. Very rarely do I write the bass line and then write the melody.

Thanks for the tips guys I'm going to try some stuff out now - and my problem specifically is making a loop sound like its just continuous playing, being repetitive is not an issue. I guess you can just tell the cutoff points just enough that it doesn't sound real.

Volume swells, man. Take that volume and turn it down slowly, to fade out. That's another one I have in my arsenal, that keeps things interesting.

I don't use computer, so I don't know the cut and paste. A lot of times I just use one of the v-tracks, or virtual tracks. And then I pick the one I like the best and run with it. Most of the time I use the original one I recorded, though... Usually has the most original. All others are usually variations on a theme.

Dont start with the first pass on the progression.
Play through your riff or chord progression at least three times and then loop the middle pass. This way the beginning of your loop will match up with the end of your loop. Make sure you are catching the segment exactly on the one. If you are using a computer and looking at the wave file you should zoom in pretty close so you can match the wave form at the beginning and end of the loop and cut/paste with precision. Some programs like Acid will automatically cut your recordings in the correct places to make it loop if you have the time signature set correctly.

As with Papa, I don't use a computer either. My digital recorder makes it easy to seamlessly loop a recording.

What kind of digital recorders do you use? I use a Boss recorder and haven't really tried to do the loops directly with it because I felt it would be no different but I wouldn't be able to see the waveform data therefore making it a little more difficult, and without being able to make easy fades I would still be dealing with my original problem of the loops not sounding authentic. I'd like to hear what you do on your recorder, and if you have some audio examples of stuff that would be sweet too.

I found when I was doing it yesterday that the best way to make it sound authentic was to play the measures once or however many times but to let the ending notes before the loop ring out - then instead of focusing on making the "perfect loop", that it was easiest to use two tracks for the looping, and fade the endings as necessary, rather than trying to find a perfect cutoff point which, frankly, I don't think exists when you have a strumming pattern. Once I had the tracks built how I wanted with fades so it sounded realistic, I just bounced them to a single track to save track space.

I also was able to discover, using the looping function on my Boss unit, that I could actually make a loop up to 30 minutes, and exploiting this I was able to discover that since it has a dedicated rhythm/loop track, that I could take my L/R drum mix and make them into a giant loop that the recorder could use on the dedicated loop track, freeing up 2 tracks of the 8 tracks normally available, thus turning my 8 track recorder into a 10 track! Nice huh?

I use a BR600 recorder by Boss. It doesn't have a dedicated loop track. What I have to do is play the loop then copy the part I want repeated however many times I want it to loop on whatever track I recorded on. It asks how many times you want to copy it so you can figure out pretty easily how make it about 3 min. This is about a 5 to 10 second process.

There is also an a/b button that will loop the enter mix between two time positions. I don't really have much use for this in recording but it's ok to test a bit out or just to solo over a chord progression in practicing or something.

I don't understand the fading bit you guys are talking about above.

Alright, right on bro I thought you were a Boss user but it's been a while so I tend to forget some details. I know the copy function of those units, I've never used them because I suppose I figured that if the phrase was not played absolutely perfect that it would not sound good enough to put into a recording - and I do know that for some reason I cannot play something absolutely perfect, even the easiest things only have to be the slightest amount off and you cannot just copy and paste it, which is what I figured the Boss units do, maybe I am wrong - maybe I just need to nail the phrase perfectly?

I don't loop anything. I start the beat out with the sample just playing, and I play my main melody rythm. I make my changes all the way throughout the song, without going back and redoing. After that I put down the harmony, or bass line. Sometimes I write a lead after that, sometimes I add vocals. After that, I go back and program the drum synthesizer the way I want the fills and loops to go.

I use the copy function to make loops all the time. Especially when I'm just experimenting with something to see if I want to really lay down a decent track. I do try to play through without looping on a final recording just for the authenticity of it and to allow those little things to happen that ensure it doesn't sound fake.

As far as having to play it perfectly to make a good loop... It really doesn't have to be all that perfect. Just play along to a click track or metro and your timing should match right up. As I said before, try to copy the second pass when recording your loop. The intro pass will always have a hard starting point that tends to jump out when you loop it. If I get around to playing my guitar today I'll try to record some video demonstrating this stuff that I'm probably making a mess of trying to describe in writing.

This is a vid of how I make a loop on the BR600. Maybe useful for the software users as well.
Don't know why there is a green block at the bottom of the video...

This is how I do it. There may be better methods for your purposes.

Full screen the vid to see the time display on the unit.