Determine if you are a Resident or a Non-Resident
There are different standards of proof for Cancellation depending on whether you are a resident or nonresident. If you are a resident, you must only show 7 years of physical presence, not 10 years.
Get docmentation for the all the years of physical presence needed
Whether it is 7 years or 10 years, you should obtain all the necessary documentation for proving you were here during those years. That would include tax statements, rental receipts, receipts of any kind, mortgage bills, insurance statements, etc.
Get documents showing Good Moral Character
Having good moral character is an element of the Cancellation of Removal for Non-permanent residents. You should get letters of recommendation from friends, family, employment and religious organizations.
Submit your criminal background check
You should order and attach as a copy your criminal background check to show what crimes if any you have committed.
Put the petition together
Now, put the entire petition together with a cover letter and organize it to put you in the best possible light.