American Express is offering an awesome promotion where if you add an Authorized User (AU) to your Starwood Preferred Personal AMEX account, they will credit your account with 2,500 Starpoints!
When it comes to earning miles/points there are essentially 2 main ways to do so -- signing up for credit cards and/or through everyday spend. I've already covered extensively why leveraging your credit through the signing up of credit cards is so valuable (big amount of points in a short amount of time!), while I haven't touched much on how to maximize your earning potential with everyday spend.
American Express currently has a targeted offer for $25 off of a $100+ purchase! This essentially equates to 25% off. The great thing is that Staples also offers e-gift cards to stores such as Target, Gap, eBay, Lowe's, Nike, etc. Even though the terms state that it is not valid for e-gift card purchases, it is referring specifically to Staples e-gift cards, with users having success getting the $25 back for the aforementioned store gift card purchases.