This is my first screener, so it might not be as good. Hopefully you will get the point :) If you have any questions about the process let me know.
UPDATE
I compeletly forgot that all these edits should be done with overrides, so when you update your k2 extension it wont delete the edits you have made.
Copy your k2 template folder located:
components/com_k2/templates/
Create this folder structure and paste your k2 template in the templates folder
yourtemplate/html/com_k2/templates/
Now when you make edits from "yourtemplate/html/com_k2/templates/" it will override "components/com_k2/templates/", and when you update k2 it wont delete what you edited. Here is some more information about overrides at joomla.org [link]
