Making up your own bass lines isn't as hard as you might think. True, you do need to know a few nuts and bolts but, once you acquire a bit of knowledge, your creativity will blossom.
I have loads of other lessons like this but this one might also interest you:
Creating Basslines Over A Chord Progression (Bm/G/Em/C)
Scroll down for the backing track and PDF.
Pop Rock Backing Track 110BPM
Chord Progression + Shapes PDF
Use these patterns as a springboard for improvising bass lines. You need to know way more than just the patterns on the PDF so be sure to learn the scales in different octaves and patterns around the fretboard.
This lesson might help with that:
Bass Guitar Scales: How To Learn And Use Them
Play in time, use articulations to add flair and don't forget to work out your favourite bass lines. You'll begin to recognise what I teach in my lessons and everything will start to make sense!
