It's a long road, and a broad question, and pretty much a duplicate of What's the best way to begin learning lead guitar?, but I have some general advice that will help.
Define your goal.
You say that "good lead guitarist", but you need to define what that actually means. Is it like Van Halen, a Jazz guitarist, Classical, Pop? answering that question leads naturally to certain entry points. There are a ton of beginner books to get you started on that style that will start you on the path.
Get a guitar teacher. They fix your technique, they know where to go and they make it far more likely that you'll practice and know what stage you're at.
Play with others. This one is often overlooked, but a big key to lead is listening, and working with the band around you. David Gilmore is a great example of this, because while he's playing sweet bluesy licks the chords underneath give it an extra flavour that adds volumes to the sound.
Best of luck!