While there are probably tomes published on free soloing, I have never heard of one. Want to scale buildings like in Assassin's Creed. Ok.
1) Go to the gym. Rent shoes and a harness, and toprope for a few hours. Be scared of falling. Congrats, you are now a gumby.
2) Buy your own harness and shoes. Start going to the gym 2-5x per week. Start annoying your friends by touching surfaces around you to see if they would make good climbing holds. Do this for 6 months - a year.
3) Buy a rope and a helmet. Take the leading class at your gym. Be scared of falling again. Start losing friends because you only ever hang out in the gym. Find new gym friends who will belay you on your climbs. Congrats, you are now a gym rat.
4) Buy a set of quickdraws and a PAS. Go climbing outside for the first time. Realize you aren't as hot shit as you thought you were. Be scared of falling again. Congrats, you are now a sport climber.
5) Save up money and take a trip to The Red/ The Verdon /Thailand after you saw your first Reel Rock. Meet people who are way, why better at climbing than you are. Start thinking of what kind of car you would like to live in.
6) Inspired by your epic trip, renew your commitment to getting stronger. Start a training regimen at your gym.
7) Get an overuse injury.
8) Realize that sport climbing is for pussies anyway. Find some guy who learned to trad climb last year who is desperate for a belayer because all his friends are still sport climbers. Be his belay bitch for a year. Recover from your injury, but acquire another, less significant, injury.
9) Climb your first trad lead. Be scared of falling again. Be told you are right to be scared of falling. Be told that the people who told you that you are right to be scared of falling are carrying their gear to the crag for no reason. Feel accomplished for climbing something 5 number grades below your highest sport grade. Congrats, you are now a trad climber.
10) Buy your craggin wagon. Apprentice yourself to a carpenter/roofer/roughneck/etc to learn the trade. Do nothing but work and climb.
11) Quit your job and leave your gym friends, sport friends, and trad friends behind (no reason to say goodbye to anyone else, it's not like they are important). Live in your car and eat dumpster food and drink lots of beer. Congrats, you are now committed.
12) At the egging of some friends in Yosemite/Joshua Tree, do your first free solo. Be scared of falling again. Feel like that 5.7 was the most significant thing you have done in your life. Congrats, you are now a free soloist.
13) Keep gym climbing, sport climbing, trad climbing, and free soloing, all at the same time. Get offered a free pair of shoes by a company, but turn them down, because you are no damn sell out (as you eat your ramen).
14) Send your proudest free solo to date. Become a living legend among other dirtbags. Slip on a V2 warm up one day and get a compound fracture of your tibia and fibula. Become absolutely broke and unable to ply your trade or climb. Move in with your parents.
15) Find an office job to pay off your crushing medical debt. Go crazy with the lack of climbing in your life. Start free soloing buildings in your free time. Realize it is nothing like assassin's creed. Realize you just wasted 10 years of your life. Realize it was still kinda fun.
16) Try to find a girlfriend who will put up with your incessant talk about climbing. Fail indefinitely.