Another little trick that I sometimes use even now, is to miss entire chords while playing.. in many cases you can play the first chord of a bar on sheet music, then just let the chord ring-out until you get to the next bar and then play that chord and let it ring-out etc.. When there are other musicians playing their parts, it really doesn't matter that much as long as it is not the guitar that is meant to be driving the song along by itself. In a 4-bar piece of music there might be 10 chord changes.. for example:

123bpm, 4/4

|| E B/E | A/E E B/E | E B/E | A E B/E ||

Here you could just play the E chord in the first bar, then A in the next, then back to E again, then back to A again in the last bar. Of course it won't song right without the rest of the band playing their parts.. and even with them, it will still not sound quite right because it is missing chords.. but it will get you through until you get used to the timing and so forth..