Santaquin Peak and Loafer Mountain form the northern end of the Mount Nebo massif. Nebo summits are a long series of weathered rocky ridge, and these two peaks form the north end, before it drops off into Spanish Fork Canyon.
There are a number of ways to approach. The easiest climb is from the road just above Payson, where it turns south to jaunt toward Payson Lakes and Blackhawk Campground. There is a sign at the trailhead marking the departure. The two peaks are only about half-mile apart, so might as well bag them both, while you're there.
There is a trail coming south from Spanish Fork Canyon, just east of the big red barn, but I have never hiked it.
The peaks can also be hiked following trails from Birdsdeye on the east, and this is the route I have followed. Amble up the Bennie Creek trail till it intersects, then turn north to the summit of choice. Santaquin Peak overlooks Utah Valley to the west, and Loafer Mountain dominates the upper Sanpete Valley on the east. Both peaks offer a hiking challenge, especially in winter, and dramatic views all around.
If you enjoy boots-on-the-ground, this is a great hike. Much easier than some of the other Wasatch peaks, with a similar exposure and dramatic views. Overall, an under appreciated and relatively unrecognized hike.