1. What made you step up and try?
2. What did it feel like?
Ah, my very first time of "FCing" happened when still in EvEUni we got wardecced by some griefers (= some 10 men corp max) and I had the glorious idea to steal a march (is that the phrase?) on them by getting a fleet all around their home system before the dec got live in the hopes they would log on, form a fleet and jump right into one of the three gatecamps surrounding the system. Yeah, totally worked. In theory!
In reality, what happened was that I was not the only one that had this idea, however the other FC "let me do it" sort of, so I suddenly had a 100 man fleet at hand which was WAY too much for me to handle and the other FC was a really helpful soul that ... well, helped me, effectively turning causing my fleet into being a fully backseat-FCed one.
Also, the WTs did not get the memo and never logged in so we decided to do a Lo-Sec roam... after getting a promising report of a gatecamp so I (we) made the 7 something jumps. With a 100 man fleet. Including battlecruisers. After stopping at a gate to wait for someone that dced to relog. The camp was of course long gone by the time we arrived though we actually caught someone else a few systems further in. Actually, my backseat FC, who was by this time basically running the fleet anyway, caught him. That stressed me out even more so my mistakes kept piling up and got progressively more stupid.
So, in short, I made basically any thinkable - and unthinkable - mistake possible. At that point I just wanted the whole thing just to end.
Edit: You should know that fleetforming in EvEUni is/was terribly formalized: First you have to announce in Alliance chat that you form a fleet, then call out for Scouts, tell them where to.... scout, then call for "Leadership", that is Wing- and Squadcommanders, invite them, call out for DPS, have your SCs to invite them, then ECM, finally Tackle (no such thing as free joining or free moving, spies!!!). Recheck with your SCs that everyone of their Squad is in the respective squadchats.
Finally you have to basically give a speech explaining some basics (update your clone, insure your ship, take ammo, who to put on the watchlist, basic fleet commands etc.). All this takes at least half an hour and often considerably longer if you have special "role"-squads.
3. What made you initially reluctant to give it a go?
The problem wasn´t so much inital reluctance, I did want to try it (at the right opportunity), rather the complete train-wreck that "my" fleet became...
4. What advice can you give to someone reluctant to make the first step and give it a go?
Don´t take advice from me how to run a fleet, I suck terribly at EvE!
If you don´t listen to me, start small, 10 people max. Personally I had a somewhat better success with such smallish fleets much later when I joined RvB (though I fucked up here as well).