Recommendation: Secure your house to its foundation (If it is not already). Secure heavy items to the walls.
Option 1: Hire an expert to secure the house to the foundation and or reinforce weak designs.
Total Cost: $0-$7000
Depending on the year your home was built, you might not need to do any retrofitting. However, we recommend consulting with an expert. Often they will do a free assessment which will often determine if your home is strapped/bolted to the foundation.
Have an expert do an evaluation on your house. Some house designs are more susceptible to earthquake damage than others and you should know now. It might take you some time to save and make the investment, but it will most certainly help with the resale here in the northwest. Many of the retrofit companies will give you a free estimate.
Recommendation: Be prepared to rebuild a temporary shelter inside your house.
Supplies: Camping supplies will work. Some tarps or plastic sheeting and a stable gun will be useful to fix broken windows.
Option 1: Tarps and a staple gun
Total Cost: ~$50
Option 2: Plastic sheeting and a staple gun
Total Cost: $35
Option 3: Tent
Total Cost: $65+
Tent - you can also find good options used on craigslist or nextdoor
Windows are not going to survive a major earthquake. You are going to want to keep the outdoor elements out of your house. Being able to fix a few windows to create a "indoor" shelter is going to be helpful. If the earthquake happens during the winter, this will be a key to keeping warm. Pick a room or two and determine how many tarps or plastic it would take to section off. Consider using your kitchen and a small bedroom. The kitchen will be nice for cooking and preparing meals and a small bedroom will be easier to keep warm even with just the heat from your bodies.