Best way I've found is to make sure you have higher-priority threats on the table.
For example, when I tried a straight green tide list with LOTS of boys, lots of Lootas, and KFF Meks, the lootas got shot off the table quickly, because their range made them a bigger threat than the boys, who were going to take a minimum of 2-3 turns to reach combat.
In contrast, when I run lootas as fire support to a speed freak army, the lootas are rarely even shot at, much less removed from play. Even raider-heavy DE, who are the most vulnerable to Lootas, find themselves unable to spare the fire power to deal with the lootas because they have 4-6 Trukks full of boys less than a turn away from charging.
So my suggestion would be to increase the number of immediate threats your army can provide, so that lootas aren't an obvious, must-kill-now unit. Add some speed (trukks, deffkoptas, bikers), harder-hitting units (Nobs, Meganobs, Kans, Deff Dreads), or distraction units (Green Baron, Kommandos).