You could be consistent and count 16th notes all the way through: 1 e and uh 2 e and uh, etc.
But you don't need to since you won't be striking a new note on every count.
With a half rest to start I don't need to count subdivisions:
1 e and uh
2 e and uh.
I can just count on the beats: "1 2 ", then come in on beat 3.
Or I could count the rest as "1 e and uh 2 e and uh" and come in on 3.
It's up to you.
Beat 3 has 4 sixteenths notes so I
do need to count the subdivisions and play on each one:
3 e and uh
Beat 4 is 2 eighth notes so I count
4 and and play a note on each count
.
Or again, I could count
4 e
and uh, but I'm only playing a new note on the
4 and the
and.
So counting 16ths the entire 2 measures would look like this:
1 e and uh 2 e and uh
3 e and uh 4 e
and uh
1 e and uh 2 e and uh 3 e and uh 4 e and uh
but I'm only playing a new note on the counts that are boldface and underlined.
So I would count it : 1 2
3 e and uh 4 and 1 2 3 4
I prefer not to count all those e's and's and uh's when I don't need to.
But you may want/need to.
You could count 4 subdivisions for every beat throughout the entire song.
But there's no need to if 16th notes only occur infrequently.
If there's a lot of phrases using long 16th note runs, you'll then want to be counting 4 subdivisions.
Rather than counting an entire song using the same subdivision, you could take it measure by measure or phrase by phrase and use whatever count is needed for that particular measure or phrase. You could even go beat by beat.
If there are no 16th notes, you don't need to divide the beat by 4.
If it's all quarter notes you don't have to subdivide at all.
You subdivide based on the smallest note value you are dealing with.