Paradise, take Pacific Ave. South wayyyyy south. past spanaway, etc.. it becomes Hwy. 7, and if you follow this, will take you to the Nisqually Park Entrance.
For Sunrise etc from the north end, take 705 to I5 North, get off at the Puyallup/River Road exit 135 and follow River Road east to the end. Take a left, over the bridge, then the right onto 167. follow this, taking the exit to 410. follow 410 east bound all the way over to the NE of MRNP. there really aren't any shortcuts.. hope this helps!