Sounds like you're learning quite a bit! Good so far!
If you haven't burned a few edges, you're not a detailer! We ALL have...
To your question. The answer is difficult, since there's SO many products out there. It depends on the car color. The darker the color, the better/more expensive the compound needed.
First, if you haven't already figured this out, NEVER buy "detail" products from an auto supply store. Not that they're all that bad, just not professiona grade. And that's the shiznit there...
Look online, and you'll find many suppliers of high quality products.
I too use 3M for cutting. But, different ones for different color cars. Again, darker cars get MUCH higher grade stuff. You'll NEVER see the difference on a white, silver, light tan, etc. car. But on a Black, Dark Red, blah blah blah car... oh yea.
I'll go out and dig up my detail stuff to give you a more direct answer.
Also, NEVER wet-sand a car that's not in DESPARATE need. A white or light car never really is. I say that because you're really just taking micron-layers off of the clear coat. Never a good idea, but widely done to correct flaws that don't extend down to the paint.
IF and
WHEN wet sanding is needed, be gentle! Start with 1500, softly. Finish with 2000 and maybe even 2500 on darker cars. Then, use agressive compound and wool wheel. Then Foam pad with 2 additional steps of increasingly softer compound.
And, Trading...
kick whoever told you to use SOFT SCRUB on a car SQUARE IN THE STONES.
Compound (in theory) is close in feel to soft scrub. But COMPLETELY different...
Anyway, sorry to randt. I just know a LOT about this subject and am always happy to help. I
owned a detail shop on the Gold Coast here in Chicago, and worked exclusively on Porsche's, Ferrari's, MB, etc for the famous here. Radio, TV and Sports personalities (MJ, Pippen, Gayle, etc) were my clients... Nothing to brag about AT ALL. I still 'cleaned' cars for a living. Point is that I have some valuable advice to lend. That's all. Just trying to help and lend a little credibility to what I say.
Again, sorry to babble a bit!
HTH
Michael