Texture for low poly model

Hi .
I have a issue about how to create best texture for low poly model.
The model is something like this :
The texture should not be too high but quite real.
Any idea ?

Use a UV map, 2048x2048 resolution should be good, though 4096x4096 is better if you can spare it.
Go to cgtextures and get the right texture, use GIMP’s normal map plug-in.