You will log in and see the screen below, and click the big blue edit button next to "Company Information" (as seen below):
You will see a screen that will be able to be edited:
Once you have inputted your information into the middle section, you can hit save. Remember to not copy and paste from a word document, because this will carry formatting into the tear sheet and will end up making the tear sheet look wrong. Typing it directly into the form will be the best way to avoid problems.
If you have problems saving it, it may be your browser. Try using Firefox or a different browser and it may take.
To change your "Company Description" all you need to do, is click the tab at the top that says "Description" right next to "Contact Information" (which is circled in red above) and you will see a similar screen.
Please refer to the notes above about not copy and pasting to avoid bringing formatting into it, and if you are having problems with it not saving, try using a different browser.