For modes all your doing is taking the major scale and starting and stopping on different notes. The're are 2 ways u want to think of them 1)diatonically 2)as tonal systems within themselve.
Diatonically;
Every major scale has 7 possible modes, here they are in order of there appearance 1)Major (ionian) 2)dorian 3) phrygian 4) lydian 5)mixolydian 6)aeolian 7)locrian
the sound quality of each mode will be reflected by the chord that is built on that scale degree (if you need help w/this, just ask)
In diatonic situations think of the modes as extensions of the major scale to help you get around the fretboard
2)tonal systems;
as musicians modes offer us choices. For instance if your soloing over a D- chord try using all possible minor mode possibilities (dorian, phrygian, aeolian)or combine all 3 into 1 scale!
remember, scales are just studies of notes played in sequence and the tonalities they create, don't take them to literal when creating. The best thing scales will do for u is train your ear to know what these things sound like. The more u play u will realize its not what you play, but how you play it. Any note will work against any chord if it is appraoched properly, if you don't believe me pick up an Omni Book & check out the music of Charlie Parker
good luck, have fun
