There are GPU servers available via remote access (ssh). Log in via one of these commands (use your faculty username):
ssh -X username@cantor.felk.cvut.cz
ssh -X username@taylor.felk.cvut.cz
Singularity images may also be located under /local/singularity_images. You can follow, more or less, the instructions for labs once you are there.

Also, please read the instructions on GPU usage. Most notably, use at most one GPU at once. Select GPU to use via environmental variable CUDA_VISIBLE_DEVICES, e.g.
CUDA_VISIBLE_DEVICES=2 my_command
Prevent using any if you don't need it:
CUDA_VISIBLE_DEVICES= my_command
You can export it to stay in effect for all the following commands:
export CUDA_VISIBLE_DEVICES=2
my_command