What you want to do is find where "python.exe" and "gsutil.py" sit on your local system, like
C:\Python27\python.exe
C:\gsutil\gsutil\gsutil.py
So hit Win+R, cmd, Enter to get into a command prompt, and do a
cd C:\Python27
Then you want to call the python interpreter on the gsutil.py file, like
python.exe C:\gsutil\gsutil\gsutil.py <COMMAND HERE>
And it should work. For your initial configuration, you would run:
python.exe C:\gsutil\gsutil\gsutil.py config -b
And a web-browser would pop open for completing the setup. There are some other nuances, but mostly "python.exe C:\gsutil\gsutil\gsutil.py COMMAND" is an exact replacement for "gsutil COMMAND" including all flags, so a long command like:
type my_list_to_upload.txt | python.exe C:\gsutil\gsutil\gsutil.py -m cp -I gs://.../ > output.txt
Will work.