What size are the dumbbells and how big are you already? I could advise some excersises, but I can't really until you tell us what dumbbells you have. Because something like should press will require a lot more weight than a lateral raise. Same goes for flies and what not.

One set of dumbells isn't enough to create a nice upper body. However, if you have a set you could do the following. Search google and youtube for videos, easier than me explaining.

Shoulders.

Side lateral raise.
Front raisers.
Bent over raisers.
Shoulder dumbbell press.
Traps. (Shrugs).

Chest.

Dumbell press.
Flies.
Dumbell pullovers.
Sit ups. (Can do these weighted with bottles of water in a backpack)

Back. Dumbell pull ups.
Normal pulls up for lat, front and behind. (Again can wear a backpack with the dumbell in or something heavy if it's too easy)
(That's the only one I can think of for back).

Bicep.
Dumbell curls.
Hammer curls.
Bent over dumbell curl.
(All basically a variation of the same thing really, but not much else you can do).

Tricep.
Skull crushers with dumbell.
Overhead extensions with dumbell.
Seated dips.

That's all I can think of. You need to have the correct weight for these excersises though, as some will require way more weight than others. All the best with them and make sure you look up youtube for videos.

Benni.