BONUS ALASKA AIRLINES MILES
Use Virgin America to earn extra Alaska Airlines miles.
If you're not already aware of it, Virgin America is in the process of merging with Alaska Airlines.
You can only transfer points to Alaska from Starwood (SPG), not Chase, Amex or Citi, making it a bit hard to accrue Alaska miles. Until the end of 2017 you will get 1.3 Alaska miles for every 1 Virgin America point transferred. My personal strategy with this was to sign up for the Virgin America credit card and do all my everyday spending, with the intention of eventually transferring it to Alaska for the 30% bonus. Unfortunately that credit card is no longer available to apply for but you can still earn Virgin America points other ways.
How to Earn Virgin America Points
Most airlines have a shopping portal where they partner with a whole list of merchants and offer varying points per dollar spent with each one. These points are typically in addition to any points that you'll earn from whatever credit card you're using, a method known as stacking. I do all my shopping at Target this way. I sign in to my account, click the Target link that redirects me to Target's webpage and place my order. The points usually show up in my account within 40 days.
I encourage you to use a great tool, Cash Back Monitor. If you have a purchase planned you can use Cash Back Monitor to search the earn rate for each portal. See below using Target as an example.