Unlike the West Rige the best way to get to the North Ridge is not! via Lake Ann, but via Three Apostle Basin.
Hike from Winfield (if you have a low clearance car) or from the end of the 4 x 4 road along the left side (east) of the creek to the junction of Lake Ann Trail and Three Apostle Trail. Turn left on the Three Apostle Trail. The trail is crossing the creek after 300 yards on a tree trunk. Hike on the right (west) side of the creek through forest up to the Three Apostle Basin.
When reaching the Three Apostle Basin, the North Ridge of West Apostle is to the right (west)of you.
After reaching the Basin do not follow the faint trail across the creek heading in direction of Ice Mountain, but stay on the right (=west) side of the creek and head up the basin until you are below the North Ridge. The northernmost point of the ridge can be reached by scrambling up the talus loaden slope to the right (west).
bring a helmet - lots of loose talus on the ridge