The approach is by bus or car to the little nice village of Majaelrayo (1.184 m), Guadalajara. Once there, cross it to the right passing the mailbox and right again leaving Club Alcarreño de Montaña Hostel to the last houses. The street converts soon to a forest trail that has to be left when passing the last house to the right. Descend lightly to the right reaching Arroyo (stream) de las Cerradillas, where the trail to Ocejón starts.
Cross the stream on a footbridge and start ascending a little, following the trail SWward. Go to the left above a schrubby hillock. Descend soon to a little dip and another little hill for reaching Arroyo de los Molinos to the right and below. Cross it on a nice bridge built with big slate slabs. Leave soon a ancient corral to the right (10 min). Traverse a flat meadow when the trail widen, start a steep slope covered with rock roses going to the left lightly on wide curve, don't follow the trail to the right that goes to the village of Campillo de Ranas (35 min).
Continue ascending the forest trail doing a sharp bend to the right. Then a little stream crosses the trail in wet seasons, there're young oaks on both sides. Follow straightly on a light slope and to the left in a wide curve. The slope become clear so there're good views from it. Do a tight bend to the right when the slope is covered with young oaks again (55 min). Ascend zig-zaging in that new oakwook. Then there is a straight section with less trees, and more creeping schrubs and meadows, reaching Peñas Bernardas (1 h 20 min).
Take an earthy path that goes plain some meters, and then to the right in a steep slope to the grey spur on the slope over Peñas Bernardas. Once there (1h 35 min) turn right to a wide gully, ascend it and reach Collado Perdices (1.800 m - 1 h 45 min). Go right over an rocky ridge to Ocejoncillo (1.940 m). This comb could be some uncomfortable when snowed but it's easy when it's dry. The path, not well marked goes on the upper part normally. It's posible to reach Ocejoncillo or descend a little surrounding its base to the left for reaching a narrow col (2 h 20 min). Push forward on the well-marked, even with some steps, trail that climbs in zig-zags the N face of Ocejón. Once on the summital ridge turn left to the survey point that marks the summit (2 h 35 min).
The descent is on the same track of ascent, but you could avoid the ridge of Ocejoncillo descending on the rocky trail that joins the narrow col and the wide bed below the N face of Ocejón. Go to the left following the path that traverses the thicket of the bed, to a meadow. Ascend lightly to the ridge and descend to Collado Perdices (1.800 m - 30 min). Reach Peñas Bernardas quickly because there is no need of trail (45 min), and follow the trail like in the ascent. The bridge built with big slate slabs (1 h 35 min) is the passing point for returning to Majaelrayo (1 h 45 min).
Crampons and ice axe are recommended during Winter, also wear warm clothes on the coldest days of the year. Do not forgive a map, compass and altimeter; they're very necessary when fog or blizzard. Also carry at least 1 liter of water each person preferably in Summer.