Work on the songs your two bands play. The two styles should keep you busy. As to tips:
An instructor, mentor, whatever, is the best tip going.
I'm sure those bands work off of lead sheet or fake chord this means the actual notes in your bass line is left up to you. Work on developing your bass line so it will fit the song being played. Reggae is going to take a rhythm beat that I know nothing about, chord tones will be the same the beat will be different.
That can be just roots or exact chord tones, i.e. for the Cm7 chord you could use just roots, R-R-R-R (C-C-C-C) or exact chord tones like R-b3-5-b7 (C-Eb-G-Bb). I find that generic chord tones let me build a groove much easier, as I'm not having to worry with what to put into the next bass line. If you need help with all that R-b3 stuff, just ask. This may help
http://www.looknohands.com/chordhous.../index_rb.html Ask for a chord then scroll the screen down to see the chord spelling.
What is a generic bass line?
Notes found in every chord so I can take that "one pattern" over all the chords in the song. What notes are those?
Every basic chord has a root, a five and an eight. so those three notes will let you play a lot of bass.
R-R-R-R - C-C-C-C
R-R-8-8 - C-C- then two C's one octave up scale.
R-5-R-5 - C-G-C-G
R-5-8-5
Any combination of those three notes let you fall into a generic groove with little effort. Chromatic runs to the next chord liven things up. How do you do that? Target the next chord's root - miss it - then walk to it and be on it for the 4th beat. Practice this using the chord progressions used in the songs your bands are now playing.
I bet the rhythm guitar - in your bands- will have fake chord. Get copies and work on that. Just that alone will keep you busy and as you get comfortable doing just those simple things - other things will become apparent.
Good luck. Simple first, fancy later usually works best.
(edit) Forgot to mention -
www.studybass.com the bassist's best friend.
http://www.studybass.com/lessons/com...ts-and-fifths/ http://www.studybass.com/lessons/com...ths/exercises/ check out example 4. In example 5 why does that same pattern (R-5-8-5) work over the Am chord? That fish thing.
