Just learn it..
I tried lerk properly yesterday and found it excelent, more than worth it's 30 res for me! I had 16 kills with it in 3 minutes without dying (mostly spikes) during one game and my umbra/scream support was the thing that allowed onoses/fades to break marine defenses (turret farms/ha marines).
New lerks need new tactics:
- do not rush to battle
- ask team to build MC first (skulks have great celerity and you can get adrenaline)
- when attacking dont stand still, fly and shoot from air, change your direction, keep your distance
- do not use spores so often, spikes much more powerfull against 1-2 marines
- umbra and scream are excelent support for teammates, dont forget spores have no effect on HA/buildings, use umbra and scream once you get more hives
I recomend these upgrades:
- adrenaline (obviously lerk needs energy to be able to fly and shoot longer, once you loose mobility you die, lerk on ground is easy to target)
- regen or carapace (i personnaly prefer new regen)
- and scent of fear or cloaking (scent of fear if marines are unorganized/have many rambos, cloaking if they seem to follow orders strictly and cant surprise you so easy)