Jaco was very influenced by soul bass playing and you can really hear that in his licks, riffs, and techniques. Black Market from the 8:30 live Weather Report album is filled with valuable lessons we can take and use in our own playing.
Check out the video to find out how.
Here's Jaco in all his glory showing us how it's done.
There are tons more videos on this site teaching how to use scales, technique, groove, and much more to create your own basslines. Keep working out as many lines as you can - by ear - and using ideas you like in your own playing. Get into this habit and you will start to develop your own unique voice.