Details
The trailhead lot is easy to find. There is sufficient parking, but it is not clear exactly how you are supposed to use it. Be inventive, but leave plenty of room for others just in case, and it will work out fine.
A trail descends gradually from the trailhead area, going down to reach the river at a location where at one time there was a dry crossing on a log jam. That option is long, long gone. So take a look, but continue left for another 150 yards or so, until you find a location where you can climb down onto a river gravel bar.

As you can also see from the view at the far side, the crossing from the gravel bar is somewhat downstream, not straight. Also inconvenient, you must climb out at the location of the deepest channel. When the water level is low, this is barely over 2 feet, and it won't matter. In earlier summer months when snow-melt water is streaming, this is 4 to 5 feet deep, and the crossing is dangerous. So be safe, and have an alternative trip plan just in case.
The trail moves straight in through river flood-plain brush, at first, then veers right and going across a marshy area where a huge hollowed-out tree has fallen. You can find a way past it — it is rotting away fast. Shortly beyond that, emerge from brush into more typical east-side dry forest, and begin the main ascent.

The trail is in splendid condition, and even has — just imagine! —
a foot bridge at a relatively messy crossing of a tributary creek.

Continue the climb 2.3 miles to reach some partial views, as the trail bends left and starts an approach toward Schaefer Creek.
There is a more gentle grade here until you pass the moist creek basin area in forest from mile 2.7 to 3.0. Then, back onto firmer dry ground, and back to the more vigorous ascending pace, on irregular switchbacks for the next mile.
At mile 4.0, reach the lip of the lake basin. The grade levels. Views
open. At 4.2 miles, reach the lake outlet pond. As a secondary camping option,
come back here and find the seldom-used camp along the south shore. This pond has its own
population of trout, if you have a way to get past the shoreline vegetation.

But continue on. At 4.4 miles, reach the beautiful south shore of Schaefer Lake. Right or left? Try the left first. There are two major camps and some additional minor ones.

Set up camp, find the shoreline, find one of the sunny and comfortable flat-topped rocks, and prepare to get lazy. An overabundance of eastern brook trout, somehow able to proliferate like crazy here, will gladly take a lure from shoreline. Check current fishing regulations.
