North Canyon Road is the main road that will take you to the Flume Trail, or just to Marlette Lake for a nice view if that's all you're up for. So, drop down onto North Canyon Road and follow the road uphill (north) for 3.6 miles where you'll come to the base of a pretty steep section of the trip. This section is about 1/2 a mile, and 300 ft. of vertical gain. This is the steepest section of trail, and once done it is down hill to Marlette Lake and the start of he Flume Trail.
Just before the top of this climb you'll see an optional road on your right that will take you to the top of Snow Valley Peak. This climb is for the expert rider only. It is very loose, and steep. It is a 1.5 mile climb with 1100 ft of climbing to the top. The view is spectacular, but it's difficult to get there.
Continue due north on North Canyon Road and you'll drop back down to a 4 way intersection:
If you go straight, you'll go out onto a point that overlooks Marlette Lake. This is a great spot to go swimming on a hot summer day.
If you go right you'll head up to the Tahoe Rim Trail section that goes over Marlette Peak, or continue on to Hobart Lake.
However, most riders will do the Flume Loop
from here - take a left and follow the trail around the south end of Marlette Lake.