When I first arrived in Los Angeles, a year after I had graduated from Boston Conservatory of Music with a degree in Composition, like most young composers who came here I struggled to get songs published and hired to score films and TV shows. Clearly, I still had much to learn. However, pretty much right away industry people told me that I had a gift for melody. Now considering that I sang early on and wrote songs from the age of 12 there was some natural talent there, but I really believe that an exercise required of us by my composition teacher, the late Dr. Avram David, made a huge difference and I would like to recommend it to you. I did this on score paper back then but you can either do it that way or in a DAW.
Our first assignment from Dr. David went something like this: ' I want you to turn in for every class for a week as many pages of free melodies, no time signature adherence required, as you can stand only using the interval of a 2nd. AND, you must try to make it as interesting as possible as we will play them at the piano and compare everyone's attempts.'
Here is a small example:
Week 1: After a week of writing this, all of the composition majors were ready to scream because it was so limiting if you wanted it to work as music. But when we played them at the piano, dagnabit, by consensus some student's attempts WERE more interesting music than others.
Week 2: ' Now you may occasionally add the interval of a 3rd, but you must then immediately go to a 2nd in the opposite direction.' See Pic 2.
Oh my... such artistic freedom, the world is ours! Dutifully, we wrote page after page but soon this too became so restrictive, waterboarding was looking less like torture than doing this more.
Week 3: ' Now you may occasionally add the interval of a 4th as well as a 3rd, but with the 4th you must then immediately go to a 3rd in the opposite direction while with 3rds continuing to go to a 2nd.'
In the words of Martin Luther King, 'Free at last, God Almighty we are free at last!'
But wouldn't you know it after we wrote page after page after page, this became maddening to the point where we all discussed carpentry as an alternative career.
Well, it doesn't take a genius to figure out that eventually 5ths, 6ths, and 7ths, were allowed and then the minor versions of those intervals, all with restrictions. After all was said and done, we did this for the whole first semester. It drove us absolutely crazy but everyone agreed that they now wrote better motifs and melodies because of this exercise. The really funny thing is that even when we started writing 12-tone music, we did so more interestingly for having done this so much.
Give it a try!