Alclad is just like the rest of modeling - there are some established solid ways to do it, but different things work for different people.
For a base, I've found that my favorite is Tamiya X-1 Gloss Black, cut with X-22 I think it is, their clear gloss. The the combo thinned down with Gunze leveling thinner. I've tried Krylon gloss black (dusted like nobody's business). I've tried Alclad's base and didn't like how it sprayed. I've used their primer, and actually really like it. Not sure I'd replace my other primers with it, but it's up their with Mr. Surfacer 1200 in terms of performance. I'd also recommend getting some Micro Mesh polishing cloths. These are my new favorite things ever, and great for polishing the surface prior to Alclad.
On my 1/48 P-51 WIP, I tried a technique I read about somewhere on the interwebs. After spraying the wings with Semi-Matte Aluminum (to represent the aluminum lacquer paint), I masked them off and painted the fuselage with Airframe Aluminum. This is one of Alclad's high-shines, and yes it is.
Once that was laid down, I went over it with regular Aluminum and Duraluminum, spraying the panels but avoiding the panel lines. The high-shine shades are all semi-transparent, which is why they need the black base, but the result is that they are also slightly darker than the regular shades, so this acts kind of like shading. I didn't mask any panels off (save for the strip along the exhaust stacks, which I masked and painted Magnesium), just stayed within the lines. After that, I misted everything with Airframe Aluminum, then with Duraluminum, to blend it all together and give a bit of depth. Overall, I'm thrilled with the results, and will be using this technique again when I get around to my 1/32 Mustangs (planning a double build of the Tamiya and the aged Hasegawa).
Also, if the upper cowl looks a bit shiny, that's because I didn't bother overpainting it, since it'll be getting painted blue anyway.
On the Bench: 1/32 Trumpeter P-47 | 1/32 Hasegawa Bf 109G | 1/144 Eduard MiG-21MF x2
On Deck: 1/350 HMS Dreadnought
Blog/Completed Builds: doogsmodels.com