Crosshair Generator
de_dust2 guides
Click to move crosshair, doubleclick to change background.
Examples: A B C
R -
G -
B -
Opacity -
cl_crosshairsize -
cl_crosshairthickness -
cl_crosshairgap -
cl_crosshair_outlinethickness -
Dot

Notes

In CS:GO, you can choose from 6 different cl_crosshairstyles (0-5)
0 and 1 have very little customizability, and can be easily done in game

Styles 3,4,5 are very similar, however, only 4 is completely static. This generator shows the preview for style 4.
Having said that, you can create a base crosshair in the generator, and change the style to either 3 or 5 with no other modifications.
Style 3 is a very dynamic (ie- expands when jumping/shooting/running) version of style 4.
Style 5 is a a slightly dynamic version of style 4.

Style 2 is fairly complicated, and currently is not supported by this generator.
However, the basis of style 2 is very similar to the generator, and you can make a basic crosshair here before editting the other settings in game.
The other settings for style 2 are: cl_crosshair_dynamic_maxdist_splitratio, cl_crosshair_dynamic_splitalpha_innermod, cl_crosshair_dynamic_splitalpha_outermod, and cl_crosshair_dynamic_splitdist