Originally Posted by: jeffhx i listen to a riff and ill just fret anywhere as long as it stays in tune...

Some would say that you're already half way to doing it right. The other half involves composing a melody based on these fingerings. When improvising around a scale, the idea is to play notes from the scale in a manner that suits the rhythm, tone, tempo etc. of the music you're improvising over. Thus, when you improvise, you supplement the structures that you're spontaneously creating, with any pre-practised structures appropriate to the style of music you're playing (eg. jazz licks if you're playing jazz, blues licks if you're playing blues etc).

...Okay, reading that again, very little of it made sense :o - but hopefully, you get the general idea!