Basic stuff:
Have an error-handling policy, and trap errors on all SQL statements.
Decide on a policy for using source code control for stored procedures.
Include a commented header with user, date/time, and purpose of the sp.
Explicitly return 0 (success) for successful execution, something else otherwise.
For non-trivial procedures, include a test case (or cases) and description of expected result.
Get in the habit of performance-testing. For text cases, record execution time at least.
Understand explicit transactions, and use them.
Almost never call SPs from SPs. Reusability is a different ballgame with SQL.
