Hello! First of all, i'm new to bass guitar. Have been practicing, chords , some song tabs, but always having trouble with finding notes fast. What is good way, maybe fun way

, to memorize all the notes on fret board? I'm really sorry, if there's any old thread like this.
I look upon this a little different than most. Where are the notes
I'll need is more important to me than knowing all the notes on the fretboard. For example:
I find my root note in first position, the first 5 frets, and then if I want to add something to that root I rely upon:
From the root it's 2 is same string over two frets.
From the root it's 3 is up a string and back a fret.
From the root it's 4 is up a string same fret.
From the root it's 5 is up a string and over two frets, or down a string same fret.
From the root it's 6 is up two strings and back one fret. Yes over the 3.
From the root it's 7 is up two strings and over one fret.
From the root it's 8 is up two strings and over two frets. Yes over the 5.
Here is what that looks like in a draft format:
Major scale box showing scale degree numbers
and the root note on the 4th string.
G~~|---2---|-------|---3---|---4---| 1st string
D~~|---6---|-------|---7---|---8---|
A~~|---3---|---4---|-------|---5---|
E~~|-------|---R---|-------|---2---|4th string
I'm sure you've seen this box with just dots
adding the scale numbers let it come alive
for me.
Now to make all that work I need to know the "note spelling" for what I need.
Major scale = R-2-3-4-5-6-7-8
Natural minor scale = R-2-b3-4-5-b6-b7-8
Major triad = R-3-5
Minor triad = R-b3-5
Diminished triad = R-b3-b5
Major seven chord = R-3-5-7
Minor seven chord = R-b3-5-b7
Diminished seven chord = R-b3-b5-b7
There is more and this will help.
http://www.smithfowler.org/music/Chord_Formulas.htm?i=1
OK back to first position. I use the C (3rd string 3rd fret) as my home base. The B is back one fret, the D is over two frets. Where is the A? Good question, you can figure it out with a little theory or just memorize first position. Here is a little theory - well D's 5th is the A so you can find it down a string from the D. C's 4th is up a string same fret so you'll find the F there. The G is C's 5th so it's down a string. Yes you will have to be able to find the notes in first position. And knowing where the notes are on the 3rd and 4th string - up to the 12th fret - is a help in placing your major scale box.
Wanting to run the major scale up the neck. Remember the spelling for a major scale is R-2-3-4-5-6-7-8. So place the "R" of the box at the 4th string first fret and the notes of the F major scale await you within the box - if you get the major scale spelling correct. G @ the 3 fret, A @ the 5th fret, B @ the 7th fret, C @ the 8th fret, D @ the 10th fret, and E @ the 12th fret. That exercise should get your fingers doing what they should be doing.
Find the root in first position and then anything you want to add can be found in the major scale box. You of course need to know the spelling of what you want. Think of it this way you had to know that 4+5=9 and 5+5=10 - your basic addition - before you could do long division. Our scale/chord spellings work this same way. IMO
Later on yes find all the C's. C at the 3rd string 3rd fret, then there is a C at the 4th string 8th fret and another at the 3rd string 15th fret. Want an octave note, it'll be up two strings and over two frets - from the root it's octave is always waiting up two strings and over two frets. The 4th is up a string same fret and the 5th is down a string same fret. Put your root on the 3rd string and the roots to a I-IV-V progression are waiting on you up a string and down a string. Things like that helped me find my way around my fretboard.
Want another G back toward the nut, it'll be back 5 frets and up a string.
Want another F back toward the nut, it'll be back 5 frets and up a string. Any octave back toward the nut will be back 5 frets and up a string.
Want another F
toward the bridge, it'll be 5 frets than down a string. My memory peg on this is the bridge is heaver than the nut so you have to go down. Nut is light so you go up.
You are playing the open string D, where is there a fretted D? Over 5 frets and down a string. Yep, our pattern once again...
You are playing the open string E, where is there a fretted E? The octave would be up two strings and over two frets. Or we will find another E seven frets over and one string up. You are on the A open string where is there another A? You have a choice; over 5 frets and down a string or over 7 frets and up a string. And then the octave up two strings and over two frets.
Play "where are you games" with a fretboard graph. The fretboard is in patterns that repeat, once you can visualize the pattern you can find most anything.
Good luck.