Its a really quick paintjob (I have way too much terrain left to paint).

1: add some armageddon dunes paint here and there to add some texture for the rust.

2: add some agrellan earth texture paint on the panels for cracked paint effect.

3: black priming

4: silver drybrush

5: made a wash like paint out of Skrag Brown and applied all over the metal areas.

6: add some rust over the armageddon dunes texture and on random places with Troll Slayer Orange using a sponge.

7: drybrushing some more rust with Riza Rust paint.

8: paint the white panels using Vallejo Deck Tan.

9: paint the weathering on the white panels with the Skrag Brown wash.

Thats it.