Three basic ideas to try for yourself

  1 - Learn to listen to your own ideas, for example say you are playing around with   a couple of chords and you like the sound of them, then you can hear another   chord or sound that should or could be included but don't know what that chord   is.  

  Try and find that chord (sound) you are hearing, even if you have to look up a   chord dictionary, do not give up.  The imagination is an interesting thing, if when   it gives you an idea and you keep ignoring it, it may slow down or stop giving you   ideas as it thinks you are not interested in what it has to say.  Now this is not a   very scientific explanation but more of an analogy to get the point across.

  One way to help you find that missing chord is as stated above knowing basic   practical theory, this can help a lot.

2 – Take any chord and a finger picking pattern that you have learned or are experimenting with, when you have it totally mastered try a variation of that pattern, experiment, for example alter the speed of the pick pattern but keeping it all in the same timing e.g.  1  2  3  4 1  2  3  4   try   1  2  3  &  4  1  2  3  &  4

 

   Click for a Tablature Example