First, use Google Maps to get you close:
Use this Google map, enter your starting address, and click Get Directions. This will get you to the corner of Sandridge Road and Joe Johns Road
Then follow these directions:
When you see Joe Johns Road on your left, turn right into the driveway that is at the intersection. The Google map makes it look like Joe Johns continues to the right, but it doesn’t. This driveway takes you into Sherwood Forest!
Google maps optimistically call the travel time around 2.5 hours from Olympia but it can sometimes be half an hour more with summer traffic unless you are driving down at night.
When you arrive you’ll see a big field on your right. Please unload near your camping spot then park your car near the entrance, on the right, as you come in. There is a kiosk near the entrance for folks to fill out the liability form and pay the camping fee.