This is an out-and-back trail that starts and ends on different roads, but you will have better luck parking on Albemarle Street NW (where I have indicated the trailhead is on the map). This is a long street with plenty of street parking, just pay attention to the signs to see how long you can leave your car there.

The trail head is hard to miss - There is a sign on the side of the road that says 'Soapstone Valley Trail' :) The trail starts off with a slope downhill which takes you to the creek that you'll mostly be following while on this trail. You do have to cross the creek several times, but the creek is shallow and the crossings are not difficult (there are rocks to walk across at all crossings) as long as you are wearing the right shoes. You will be in the shady woods the entire time and you may even forget that you are in the middle of a city.

About halfway down the trail, right after a stream crossing, you will see a steep set of stairs that take you up to a paved road with a very cool-looking house in front of you. You can either go right here to continue along the trail to the end, or you can go left along the paved road which will take you back to an earlier section of the trail, creating a lariat shaped hike.

The hike ends at a busy street called Broad Branch Road. Be careful here as cars drive by quickly and there isn't much of a shoulder. Here, you can either turn around and go back, or cross the road into Rock Creek Park and continue onto the Western Ridge Trail.