Hey here, I`m pretty new with Zbrush… no hate, no flame! 
Right now I`m trying to create something like a leather strap for clothings and its always looking irregular, odd, wavy and unprofessional.
I attempt drawing a mask and using the panelloop-function or adding a cube and stratch it but Im not satisfied.
Is there a way to create and edit simple geometric forms like this rectangled strap?
Thanks in advance!
Hey Feuerputz, the CurveStrapSnap Brush will do exactly this, make a strap. Just draw out a curve onto a mesh with no subdivisions.
To interactively adjust the size, just change your draw size and click the belt again, and it will update.
If the strap is high off your mesh, you can adjust this with Imbed slider, found in Brush > Depth. A setting of 0 will sit right tight on the mesh.
You can also adjust the shape of the belt by hovering over the curve line and you’ll see your cursor changes to a blue ring. Pressing S (brush size) while it’s active will change it’s size, makes it quite easy to manipulate the shape.
You could also use the zmodeler brush with the bridge function, but I think the CurveStrapSnap would be more flexible for you.
Hope that helps ~ Cheers ~