Hey 63Chevy!
The trail is fairly straightforward and, depending on your start time, there will be others gathering in the parking lot that you can follow. Once you park in the lot, start walking up the fire road. Below is a detailed description of the hike from one of guys I hike with. He is leading a Meetup this Saturday on that trail and I copied the info directly from his posting.
His group will be descending via the Devil's Backbone Trail and he estimates the total hike time to be 7-10 hrs. I prefer going down the DBT, but that is best when you have another person with you so that you can leave a car at the bottom of the ski lifts to get back to the Village where you started. Hope this helps.

The trail begins about 100 yards south of the NFS Baldy Visitor Center and behind the church.
To reach the trail head we proceed up a road for about 1/2 mile passing by some extraordinary private homes nestled in this beautiful canyon with a year long stream. Its easy to see why this road was the first to be settled in Baldy area. Once we leave the cabins behind the real hike begins.
I like to see this hike in roughly four parts:
Part 1 is the relatively easy to moderate initial climb out of the village. The first half of this section is shaded with oak and your typical Southern California vegetation as it follows the creek canyon. This section ends (mentally anyway) when you reach the lush open area of the Bear Flat camp site. Note: There is no water past this point.
Part 2 is basically switch-backing up a steep east, south-east mountain slope. The switchbacks are quite numerous, and your goal should be to ascend this section before the morning sun gets to work as the trail is totally exposed here. It's not a particularly pleasant hike at this point.
Part 3 begins as you top the east facing slope and start working up the ridge-line that will take you much of the way towards the summit and into the alpine forest zone. The grade is steep here, and as you progress, quick rest stops are perfectly OK to let your leg muscles stop screaming. The views on this section are actually quite stunning, with vistas of all the surrounding San Gabriel ranges. You will pass through two or three mountain saddles with relatively level ground and some shaded areas on the way, but frankly, its up and up and up for most of this hike.
Section 4 takes you to the summit and here you will transition out of the alpine zone and into a mixed alpine high-altitude environment with lots of ground-up decomposing granite. You will cross a razor back ridge that presents no problems in the summer time and proceed on up to the final push to the summit. Don't be fooled by what seems like your first glimpse of the summit, you are actually viewing West Baldy. As you approach, you will actually be traversing along the slope of West Baldy before beginning the final push to the Mt. Baldy Summit. Keep a sharp eye out for the trail marker and bear right to reach Mt. Baldy proper. You will soon see piles of stones built as wind shelters in the distance as you look towards the summit. That's where you're headed and you'll be there in no time!