For me, to learn a new bass line it’s repetition over and over again until my muscle memory kicks in. I always have music infront of me, but since I can’t read music, I use either tabs I’ve found online (and 99%of the time I’ve corrected and modified them to create my own), or I create my own tabs (ugh—so laborious).
If I’m NOT using tabs (which is probably 2/3 the time now):
FYI: I do not read music.
I also create funky notations over a page of lyrics and chords that the guitar players in our band use. Before my intros on my music I’ll have a “notes“ area—I’ll write out typical bass patterns used in the song and label them “Pattern 1”, “Pattern 2”, etc. For some songs, I’ll just write, for example, “Pattern 1….” over the verses so I don’t need to write it out a bunch of times, and I write “Pattern 2….” over the Chorus for the same reason. I add the “…….” after my pattern is identified to signify that I repeat that pattern until I come to either the next pattern or a place where I have actually written out notes for a bridge or other tricky part. All of this includes lyrics for me because I find them very helpful, especially during a gig if I happen to somehow have an errant thought and find myself momentarily confused about where I’m at in the song.
I also use a weird shorthand I came up with to compensate for not knowing my fretboard cold (even though I continue to try to embed it in my brain). I write the root note above the lyric in which it is to be played, but sometimes I also use a superscript to identify what string I am playing that note on (in addition to a subscript for the counts, if I feel I need the reminder). For example, F with a superscript of 1 (sorry, I can’t type that out on my phone for your visual), means I play the F root note on the E string, which I have called the 1 string. The reason why I do this is because a song might call for a lower F in one area, yet a higher F in another area of the song later on, so I’d label that higher F as F with a superscript of 4, for example—F played on the G (4th) string. Because I do play on open strings occasionally, I either totally leave the those notes with no superscript (to signify it’s open) or I use a zero for the superscript.
Another approach I use to help me visually during a gig, because I always have music infront of me, is I color code my music parts. Intros, instrumentals and outros are green. Choruses blue. Verses red. I do this with my tabs as well. And I put lyrics under my tabs. All of these cues help me to be where I’m supposed to be—especially on fast songs.
Clearly, I’m not a master bass player, but we find ways to compensate, when needed. I’m playing out, so it seems to work ok for me. However, my spontaneous ability to play is sorely lacking, so far. But I am able to play the original bass lines for what I feel are fairly challenging songs like Rhiannon (Fleetwood Mac) and Bus Stop (The Hollies), for example, because of the methods I use. Yes, much is memorized by the time I play a gig, but the truth is, I cannot rely on my memory, and I can get an errant distracting thought, so the music infront of me is necessary.
Hopefully someone out there can benefit from the newbie (and not so newbie) tactics I’ve employed. I continue to learn—there’s so much to learn, isn’t there?