My computer is running slowly

Restart it. Computers that are never shut down slow down over time. Restart at least once a week.
Close what you're not using, especially browser tabs and large spreadsheets.
Let updates finish. A computer is often slow straight after updates install; give it a restart.
Check free disk space. A nearly full drive slows everything down. Delete or archive files you don't need (but ask first about anything shared).
Note when it happens. Slow all the time, only when starting up, or only in one program? Put that in your ticket; it narrows things down quickly.