Yeah that video is useful. Despite not having seen it before, that's how I learnt to Squad Lead (and still certainly learning). I started by acting as SL for trans as that is a pretty manageable role as long as you have decent pilots and people who aren't spamming the mic.
(Had to tell my squad to shut up a couple of times yesterday as they were constantly talking and I couldn't hear the comms traffic coming from local and from other squad leaders.) So make sure you're being assertive in this regard as direct communication is key. Obvious there can be moments of downtime and that's fine, but that should be dictated by the SL and not by the squad.
Currently i'm trying to get better at leading small groups of inf, hence you'll sometimes see a squad called 'Brimstone' which is me sort of practicing the intermediate role by acting as irregular infantry and as someone said previously, essentially giving the enemy somebody else to shoot at so the veteran squads can have an easier time.
I remember reading a passage from Max Hastings; a war historian: "95% of the infantry are simply there to be shot at, it's up to the 5% on both sides to act decisively." I feel the same way in PR and every bullet that gets fired my way instead of in the direction of the veteran squads is a win win in my opinion!