Not to bad really, but lets start with the basics.
The render you have used for this is really low quality. Pretty much anytime you use a low quality render the final result will also look low quality. If you are wondering why I say the render is low quality, its because for the most part it is blurry in areas and lacks in color for you work with. So for future work try to find a good quality render.
I also think the render is too large for the canvas size. When resizing your render, make sure it matches the dimensions of your canvas. For this particular tag the render needs to be a bit smaller, it will allow you a bit more room to add your effects with out it looking cramped and messy.
Because of the render size, its very hard to see what you have done in the background. Thus making the tag look less exciting and takes away from the whole atmosphere, because its all render pretty much. So this part goes with the bit above about sizes.
You also need to count for flow in a tag, to make things easier for yourself try to find a render that has some natural flow to it for you to work. In all fairness this render does have some ok flow to build a tag around, but again due to its size you took away that option really.
I see you have tried to give the tag some depth, but if I am going to be honest it hasn't really worked. There are many elements you need to use to create good depth in a tag. Yes blurring is an important element, but blurring on its own will only produce a false sense of depth. So when blurring try to have different strengths of blur, for things you want to appear far away try using a 0.8px gaussian blur, and for things not as far away use a 0.4px guassian blur. Finally for things close to the render leave them without any blur, now this is just for starters. Next you want to add highlights and shading to the right areas of the tag,(this will take time and practice to get right.) It also plays an important role when creating depth. Finally gradient maps(adjustment layers) will complete the illusion of depth you need to select the right colors to use and the correct blend modes to place them on.
There is a lack of lighting in this piece, lighting helps give a sense of realism in a tag. When working on lighting always look at the lighting on the render first, this will always tell you where the lighting needs to be placed. For example if the lighting is on the right side of the render, it would be pointless to place the lighting on the left side of the render. Also remember that many renders have several places where lighting will hit them, so you will often need to work with 2-3 light sources.
Effects are always a must in signatures, and there is more types of effects than you can poke a stick at. But just to name a few and more commonly used effects, these would be fractals(mostly for lighting effects,) c4d's(can also be used for lighting but mainly for depth and composition purposes) and c4d bubbles(mainly used for lighting and composition purposes.) Pen tool is becoming ever so popular to use now as well. All of these things take time and practice to learn to use the correctly so just keep trying you will get it eventually.
Sorry this is all I have time for, but to help you even more I will post a link(my photobucket page) to a fantastic guide for you to read over. It is long but well worth the read, I used to have it open everytime I made a tag when I was learning. It covers the basics and also has a small tut at the bottom. Anyway I hope this helps you in some way
Photoshop guide:
You must be registered for see links
