Ok, so here we begin with the basic chords upon which I built my melody. The key to any strong melody (at least in my experience) is to be able to sing it. If you work out a melody that you aren't able to sing, you can also be sure that a vast number of your audience might not experience this melody as being very melodic, they might rather think it to be a solo or something to that effect.
This is not saying that rhythmically and harmonically advanced melody-lines are bad, I'm just saying that a simpel melody (regardless of harmonic context in the background) will almost always come across as more memorable and melodic.
In this part you can see how I start out with the basic chords of Bm, G, D and A, and sing my melody on top of these. This is the way I most often find my best melody, taking any riff or idea back to basics, and letting my ears guide me towards a simple and effective melody. As the harmonic structure of the chords develop, so can the melody, but still retaining that simplistic, strong melodic content.