What is your subject matter? I'm no expert, and basically skipped the hobby since Y2K so I too am learning a lot of new techniques. I ask because I think it matters.

Figures for example, seems that most pros, or the ones on YouTube, prefer multiple colored glazes (as many as 10!) on top of a black&white undercoat with highlights.

Aircraft and armor might be more similar to each other, but the latter are generally much more abused and weathered. I do think your question about steps and layers could be the same for them.

Since my break I've done 4 aircraft, and am working on my 1st armor since the 1990s, I am not one of the pros you are asking for, so YMMV   Here's what seems to be working for me so far.

• Base coat of 1500 surfacer (I prefer black for panel lines)
• Mottling and highlighting with White Testors MM (stay out of the panel lines)
• Top/color coat of acrylic (I'm using Tamiya due to trust of the brand since the '70s)
• Mix a little light color in the cup you just used and apply panel highlights (stay out of the panel lines)
• A layer of acrylic gloss varnish (for the decals and the washes to come)
• Decals
• Another gloss acrylic to cover the decals (and help hide edges)
• Then multiple washes
  • I've used heavily diluted enamels for detailed stuff
  • I've used artists oil paints for larger less detailed areas (rub off excess with swabs or even towels)
  • Start with lighter than you think colors, easy to get darker if needed
• Then I typically apply a matte coat to the entire thing before adding canopy, but when painting is complete
• I do not do anything special to the clear parts, but I've seen some people use floor polish, and I've seen others use actual polishing compound with elbow grease

Hope this helps, I'm sure the vets will come in and help too.