fascia
As I understand it, one should pre-drill the hole for the fastener to prevent dimpling.
I am new at this so any lessons-learned or pitfalls to avoid are appreciated.
Assuming that you have one-by (3/4" nominal) fascia, I'd install steel wraps. They're commonly used in my area's harsh climate for an attractive, maintenance-free finish. Two sizes are available (for 6" and 8" fascias), but you could trim the top edge as needed for non-standard heights. The only preparation you'd need to do with your existing fascia would be to flatten out any warpage and replace any rotten areas with raw pine lumber.
Be aware that this product is installed by sliding it under a metal roof edge, and that it's nailed upward from the bottom along the narrow edge. Nailing the face (other than at joints, where needed) results in dimples that stand out in certain lighting conditions. Lap pieces such that the lap is less visible from entryways, etc., and so that water flows properly on rakes.
I'm not sure what sort of edge treatment you need at the top, but fascia and other light sheet steel can be cut with a sharp utility knife.
With clamps or a helper, lay a straightedge on the back side of the fascia and score along it with a new knife blade. Knife angle is important and can cause your cut to run astray. Keep things in line. Run the cut twice more, then remove the straightedge and snap the metal along the cut by flexing it.
If it doesn't fold on the snap right away, and cleanly, score the metal again with the knife. You only need to get maybe halfway through the metal for it to snap.
If you know someone in the siding or HVAC business with a brake apparatus, cut your metal a bit wide and have them hem it to the final height. A hem provides a safer workpiece and a nicer finish.
Best Answer
Fascia wraps should only be nailed on the bottom (horizontal) face if possible. Avoid nailing the vertical face except where the run terminates if you have a gap, and then use a single nail. Dimples in the vertical face are very difficult to avoid and show conspicuously in certain lighting conditions.
Most carpenters don't pre-drill, but it can be difficult to penetrate the metal if you're not skilled in upside-down nailing. Feel free to do so. You might even do it on the ground beforehand. Aim for the center of the face and every 16" to 24" or so.
Be sure to use corrosion-resistant nails in a matching color. Drive them just far enough to pull the wrap into position. When working with finish metal, gentle is the name of the game.