All good tips...but I'd recomend staying away from the 3M #77. It doesn't hold up well in the heat, doesn't stick well to smooth surfaces, is so fine it's a MAJOR mess to work with (that fine mist gets in your arm hair and...well it's just nasty!)
The #08088 "General trim adhesive" is just as easy to find (they carry it at walmart...$12 a can last time I checked and you probably won't use a full can) and it's MUCH easier to work with and has a MUCH stronger bond to the vinyl and the aluminum or paint.
Be sure to spray both sides and let it set for about 10-30 seconds depending on the temp (warmer weather 10 seconds, colder weather 30) so it's no longer wet but still sticky. And get it right the first try because that stuff will STICK...you can pull it up...but it won't be easy and you'll probably stretch the vinyl.
Oh one other hint. Lay the vinyl out in the sun before working with it or if you're in a hurry hit it with a hair dryer. When it's warm it's more flexible and any wrinkles or folds will go away.
Two more hints....if you want a softer effect go to a fabric store and ask for headliner material. It's kind of pricey but a layer of that first will give a nice "padded" effect. You can also layer it to make designs but since it's soft it will be kind of a ghost effect.
For more pronounced texture (like flames or lettering) pickup some sculpting foam at your local craft store (sometimes walmart will even have it in their craft department.) It's like $0.70 for an 8x10 sheet and is a fairly sturdy 1/8" thick material. It's soft enough to be dented with your fingers...but firm enough to stand up under the vinyl and give a 3D effect.
The oval around the YumaDuners.com logo on my speaker box was done with headliner material and the logo itself was done with the foam. The whole thing also got a layer of the headliner material since I got a remnant that had stains on it for next to nothing. It was a >$20 piece that I got for a couple bucks! What did I care that it was stained, I planned on covering it with vinyl anyway!

It's really not that hard even if you want to get fancy with it