when i was about 14 afew of us decided to start a band. i couldnt play anything so decided to play bass. the guitarist had been playing since he could hold a guitar so he gave me pointers on getting started. once i could play a few riffs, and knew the basic notes i was bought a tuition video for slap technique(!!!!) and set about learning that. i learnt what woked mostly from jamming for hours with the band(our parents must have hated us)
after a year or so i got an acoustic guitar and learnt the basic chords so i could help more with the song writing.
im 26 now and didnt really play lead guitar until about 6months ago and have been teaching myself as many techniques/exercises as possible.
i would recommend playing with others as the best way to really learn about developing your own style/sound as the dynamic of how you play relies on your interaction with other musicians as much as learning techniques.