In my opinion, and I'd like to hear Sam's on this too, but I would recommend you take Fundies sooner than later.
It's easier to learn good things sooner rather than having to re-learn or break bad habits later on.
Ideally, it's best to take fundies early so you do not develop too many bad dive habits but I believe everyone has to come to fundies on their own terms and in their own time. Factors like cost, time, work and personal commitments have to be considered.
For beginner who cannot take fundies right now, I strongly recommend just hovering at the student platform (25-30 ft) of your local quarry or a swimming pool until you are comfortable with hanging in the water column without finning, just hanging in a horizontal position. Don't recommend doing this in the open ocean as currents would seriously task load a beginner.
If you are comfortable doing that then slowly task load yourself while trying to stay in the water column without changing your depth keeping your trim and buoyancy. By task loading I mean starting out slowly, reaching and touching all your various D-rings, your D-ring, not your buddy's crotch strap D-ring.
Clip and unclip your reg to your D-rings, clip and unclip your SPG. Do all this without compromising your trim and your buoyancy. I assume the diver is diving a DIR rig with the D-rings and the bolt snaps. Switch from your primary reg to your octo without changing your position in the water.
I can go on and on but you get the general idea. You will need these skills to do S-drills, valve drills, deploying SMB and donating your reg to your buddy. Once you have your trim and buoyancy down you can concentrate on the drills the instructor will throw your way.