Hey
I’ve been working on cloth physics lately and an idea that i had was a small silk napkin in a martini glass. i know the idea may be weird, but i feel that the lighting and texture of the cloth came out well. rendered in cycles at 350 samples. tell me what you think. all comments are welcome for critiquing. Thanks and enjoy!
Im guessing that this is your first project?
A few thing…Firstly, you want to set the shading of your model to smooth…I can’t tell about that glass, but I can see the individual faces of the cloth.
You should also work on the lighting, atm it looks like you have a point lamp right above the model? Try and use some emission planes. Also, make a backdrop for the scene. Even if you want to just show off the cloth/glass, being able to see the edge of the square and the environment isn’t very attractive.
Something like this perhaps?
Easy to model, give it a white diffuse material, and place the contents of your scene inside it. It gives you a nice clean background, and shows off the model better 
Finally, just try and liven it up a bit…make the scene brighter in general.
Good luck on future projects!
Your image reminds me of a tutorial I saw. Take a look at this and I think it will give you some great inspiration and tips:
Keep up your efforts!