How do you actually choose a Presidential candidate? Aside from the fact that the two main political may change some of the process due to the virus restrictions currently in place, there is a process for each party to select their candidate for the general election for President of the United States.
If you are a Republican, this link to the Washington State Republican Party will provide the details for the selection process for delegates. It is the delegates that actually select the nominee. The delegates are proportioned according to the vote for a particular candidate in Washington’s primary election.
If you are a Democrat, this link will let you apply to be a Democrat Delegate. In Washington, several Democrat Candidates dropped out just before the primary, but their names were still on the ballot. This led to some possible delegate votes to be available to switch to a different candidate. Warren, Buttigieg and Klobuchar voters, might switch to either of the remaining two.
Of course, there will be many of you who are exhausted of it all or have no whatevers to give. You are not helping, but someone will step up to choose for you.