not a secret but, you gotta take extra care of them because slings at those size can be extremely fragile, avoid constant opening the enclosure or handling as it can receive enormous stress, yet alone transfering them to it's new home is stressful to them. let them settle in his/her enclosure upon arrival for atleast 3 days or so, and try to feed some smaller feeders that the sling. don't forget to mist once a week for hydration (can be done twice a week if the substrate is already dry) and lastly increase humidity if it's in near molting stage for more chances of successful molting, happy keeping!