1. First Open Cinema 4D and make a new document. Now, create a sphere primitive (Objects > Primitive > Sphere). You should now see a sphere in your main view port. This is what we will be making our abstract from.

2. That was simple enough, wasn't it? The next step is to make your object (the sphere primitive) editable. To do this, right click the sphere in the main view port, and click "Make Editable". Nothing should appear to happen, but this step is crucial and must be done.

3. Now, use the polygon tool by pressing the button highlighted in red:

4. Now for the fun part. The next steps are all about experimenting, I will just cover the basics on what you need to do. First, right click your sphere again, and click "Magnet"

5. Now, left click on parts of your sphere, and start pulling them outward. By holding the shift key and pulling out at the same time, you will make the surface more even (some times this is the best way to do parts of your sphere to make extrusions like spikes), but you don't have to hold shift the whole time. This step really is to just make your sphere look nothing like a sphere anymore, It doesn't have to be too complex... yet.

6. Now, right click your sphere (or what used to be a sphere) and select "Bevel".

7. Now, left click somewhere in your sphere and start pulling your mouse out. WOW! AMAZING! Bet you didn't think it was this easy. Do this until you have a decent about of jagged objects coming in and out, then stop. This is not the final step yet...

8. Right click your sphere again, and select "extrude inner". Do what you did in step 7 except with the extrude inner tool selected. Now right click your sphere again and click extrude. Repeat the steps again except with this tool. Now go back to your bevel tool and keep playing around with it until you find something you like. You can keep repeating using all of these tool as many times as it takes to make a nice abstract render. Here is how mine looks:

9. Now this is just a simple abstract, its up to you to keep playing around with settings and modifiers. I hope you got something out of this tutorial!

Now save it and you have your own 3d abstract!