At the trailhead, you may want to take time to examine the west and southwest flank of Twin Sisters West, identifying cliffs and areas of talus you may want to avoid later on. From the trailhead for the Rico-Silverton Trail, head south for about 2/3rds mile to the open area on the USGS map identified as "South Park." The "park" comes shortly after crossing a tributary side stream that flows from the west facing basin between the two Twin Sisters summits. In early season, unless the Forest Service has constructed a "bridge" of some sort in recent years, stream crossings may be difficult, especially when you initially have to cross to the east side of the South Fork. The flat meadow can be rather boggy as well and you may encounter more bogs in South Park. From the park, ascend SE, leaving the trail, up the steepening hillside through trees to something of a bench area between 11,600 - 800 feet, mostly covered with rock talus. From that bench, ascend even more directly to another bench or small bowl at 12,100 ft. where contours open a little. This is a little north of directly west from a saddle south of Twin Sisters West.
Continue your ascent on ever steepening terrain into a shallow couloir that will lead to the saddle just mentioned. 800 feet of more gain will bring you to that saddle. If later in the season, most of this will be on unsteady talus. Early season climbers may find the couloir snow-filled, thus avoiding much of the talus, but ice axe will be handy and you'll be doing a lot of tiresome kick-stepping. Once at the saddle, walk with greater confidence to the summit of West Twin Sisters over a much easier ridge. To climb Twin Sisters East, continue from the west summit NE, following the connecting ridge to Twin Sisters East, the higher of the two summits. The traverse will take about a half hour. The descent to the connecting saddle will be on some tundra with more rubble and talus. The final ascent will be mostly more tolerable rocky rubble.
If you're contemplating or actually working on climbing all the 13ers, then continuing on from Twin Sisters East to UN13,042 (V7) would make a great deal of sense. If not, you can return by the same route as you came or return by the following alternate route to climb these two summits and V7:
Alternate Route: Use the route for V 7 that is actually a segment of the Hard Rock 100 endurance race. If using that route description, you will ascend Twin Sister East first, then traverse over to the West summit.
From the summit of Twin Sisters East, you can easily traverse over to Twin Sisters West and return, taking only about an hour to do so, over mostly rocky conditions.