The easiest approach would be to take the Shadow Creek trail exit off the John Muir Highway toward Lake Ediza. One could also access the route from Garnet Lake via one of the lower "saddles" on the Eastern slope.
Start in a couloir that is just North of a chimney, in the middle of the rock face and ascend 3rd-4th class rock. Once you are above the chimney head into another couloir to your left and progress onto the steeper sections of the climb, then move back toward the North (right) to a ledge (depending on the season there may be a snowfield here). From here head right to get underneath the summit ridge. "Gain the Ridge" and the summit block will come into view. There is a photo on the "Banner Peak Photos" page of Banner's South and West sides. A much better photo of this particular route is printed in RJ Secor's High Sierra: Peaks, Passes and Trails guide.
I did this route in mid July and found everything to be dry that particular year, though this is not always the case. Early season climbers may want an axe. I haven't seen the described snowfield, so any additions here would be a help. This peak is remote when compared to the accessability of peaks to the East, making even the easier routes an adventure. A rope, harness and helmet should be carried by anyone who doesn't consider themselves a soloist.
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