The most direct route to the summit is via the West Ridge from Spider Formidable Col. The ascent is apparently not difficult (Class 3) but the rock is nasty. From the col it doesn't look inviting other than the shortness of it to reach the top.
Instead, the easiest route is from the south side (this is called the Southeast Route by Fred Beckey in his guide but it really goes up a gully due south of the summit). The route makes use of a gully (or two) and, depending on routefinding skill, should not be harder than Class 3 with the odd Class 4 move.
The final summit tower looks improbable as you look over at it from the crest to the east but it's merely easy Class 3.
Approaching the Gully
From Spider-Formidable Col, descend from the narrow eastern notch down steep snow or in the moat beside the snow for about 150 vertical feet until it is feasible to begin contouring left (east). Continue eastward over talus slabs and snow then heather and minor rock outcrops to reach a minor basin/slope below Spider's Southwest Face.
Now the traverse gets tedious. Aim to descend around the obvious buttress a quarter-mile distant. The gully you want is on the other side. The traverse across is over some of the steepest, hardest dirt imaginable. Some of it is actually pretty sketchy. I suppose you could descend farther down to heather but that will require losing another 200 feet or so. There are also one or two washout streams to sketch across. Eventually, you will round the toe of the buttress (7,200 ft). On the other side is another heinous washout stream and unscarifiable slope. Fortunately, you can get into the gully on the left side (beside the butress).
In the Gully or on the Rib
The gully starts here. It goes almost all the way up to the summit crest but you won't want to stay in it for long.
Initially climb up the left side of the gully (one Class 3 step that could be wet) until it narrows. If you're looking for adventure, stay in the gully where several short Class 4 steps interspersed with ordinary scrambling will greet you. The easier option is to mount the rib to the left of the gully after about 200 vertical feet has been climbed. This will be beyond the initial Class 3 step. Once on the rib, climb up and up and up (Class 3) until the rib (and gullies to left and right) merge into one wide taluscree slope. Imprecations will work well to get you to the final crest immediately west of Pt. 8286 (the east summit). The true summit is to the left.
Final Crest Scramble
Walk the easy Class 2 crest to a knob that provides the first view of the final summit tower. Don't cuss. The tower isn't nearly as vertical as it appears.
Descend the south side of the knob then move rightward to the notch. You will now see the tower is nothing to be concerned about. At first take to ledges on the right side then re-mount the crest all the way to the summit. Class 3.
Time = 2-3 hours from Spider-Formidable Col; 4-5 hours round-trip
Gain = ~1,200 ft; 1,400 ft round-trip
Return the way you came up. Avoid the upper gully. I remember a rappel sling or two but there is no need to even go there.
Ice axe (early season only)
Lightweight crampons (especially to descend the snowfinger on south side of Spider-Formidable Col if no moat is available)
Trekking poles (will probably be handy for the tedious traverse across the south slopes)