This is a popular hike for a good reasons--great trail, near Seattle off Exit 38, great views, not too crowded.
I have seen 3 different trail descriptions, none of which are really correct or easy to figure out, so here it goes:
Once you are off the John Wayne Trail, there are only 3 intersections. The first one is signed MT WA, as described in the WTA description. It goes right. The left there, signed Sallal Point goes in a short way to sport climbing crags (some very good routes there too). The second intersection, also signed for Mt Washington, goes right again. The left there is signed Great Wall as the WTA description says. The third intersection comes as you come up over a short rise in the trail to a "T". There is no sign here. Directly in front of you is a swamp with dead trees in it, etc. Go left here, which is the most distinct trail. The right one goes over a culvert and someone has been clipping some brush there, so it looks like it may be an established trail. But it's not the correct one. The correct left one has a cairn base of several large rocks in a pile on the right as soon as you turn left.
That's it. There are no other intersections but these three once you are past the JWT. I think the WTA description needs some updating. The meadow you "burst" into is just a fairly narrow ledge slightly wider than the trail with talus on the uphill side. It is a nice snack spot. I have no idea where the "sharp switchback" mentioned is. There are countless of those. There is just one sign about the watershed, only a few minutes from the summit.
All in all a great hike, esp for February! Total time up 2:40 (for this 66 year old) with several stops for snacks and chats. Many of you younguns will be faster. I took my time, greatly enjoyed it, and was back at the car in under 5 hours total. I saw 10-12 others on the trail. I enjoy seeing all the hikers out getting after it and really appreciate the WTA for their hard work and advocacy!