I am not going to explain you how to bend - there is a lot of articles about it, so find it. So the thing you need to improve your bending is a guitar tuner which can tell you that is the note you playing.
So, pick the third string on the 14th fret and bend it. It's an A note, make sure it's A - check your tuning. So too make a clean full bend you need to bend a note to B note. So bend it until tuner shows B. Remember this sound, do it without a tuner, then with a tuner again, do it until you get your bend right. Practice this thing as much as you need. And then you can do a full bend clean - that's great! Good job man!
Now you only need to practice different bends on different strings, full bend means - you bend a note to a note 2 frets down the fretboard. This is the note you want to reach. To do a 1/2 bend you should bend it to a note which is 1 fret down. For 1.5 bend - 3 frets down and so on. 1/2 of the bend means one fret.
So this is the way you bend clean! Now if you have spent much time practicing bends, you can't do them clean easy. Awesome job man!