Notify Your Landlord in Writing of the Substandard or Dangerous Condition
Even if your landlord has personal knowledge of the problem, write to them at the address where you pay rent and notify them formally that they need to make repairs. Identify the problem specifically, e.g. "The septic system is leaking in the basement" or "we don't have any heat" or "the electricity is not working right".
You have to create a paper trail. You have to be able to show the Court that you gave the landlord a chance to fix the problem.
Keep a Copy of the Notification Letter
Wait for the landlord to respond - or not. Your landlord has 24 hours to start fixing immanently hazardous problems.
Take a Copy to Your Local Government, and Demand They Inspect the Premises
You have to know whether you live in the City or the County. This is not always obvious. If you go to the wrong municipality your response will be delayed. You have the right to demand they provide an inspection. Your authority is RCW 59 18 115 and RCW 59 18 085.
Some places are going to look at you blankly and tell you to your face, "Oh, we don't do that." YES, they do. The trick is to get to the right person. You want a Building Official. If you cannot determine who to ask for help, you may want to contact an attorney to help you.
Be Available for the Inspection
Once you have asked for help, you have to be available so they official can get into your unit. This is just so the official can certify if the condition you are complaining about exists, or not. This is not how you get your landlord to replace your carpets, this is what you do when you don't have a functioning sewer or safe electricity.
Wait for the Inspection Report
Once you receive it, you can determine whether you have standing to ask for a relocation remedy. This is $2,000 or three month's rent, and all your costs and reasonable attorney fees(!) If you are entitled to it, you are entitled to receive it within seven days. Your landlord is supposed to pay it, but if that doesn't happen, you can request that the city or county pay you instead.