Welcome, and congrats on your new pet.
The sound in blue tongue skinks is referred to as huffing rather than hissing. Huffing is very normal and can be your skink's way of expressing to you a wide variety of emotions.
Not knowing the species or age of your skink it's hard to guess whether he might be trying to brumate or not, but to make sure they don't go through too much additional stress after moving into a totally new environment, we suggest you mostly leave the little (?) guy alone for a few weeks to acclimate himself. Put in food for him, change his water, check temps, make sure he has ample places in the different temperature zones where he can feel secure enough to hang out where he needs to, to control his temperature. Other than that, no need to worry about "taming" until a later time.
Check out the links here:
viewtopic.php?f=4&t=27721 to make sure you've read through all the pertinent information so you can get off to a smooth start with your new buddy.
Good luck, hope you have fun watching him discover his new home, and we're here if you have any questions after perusing the "start-up" info links.
Let us know how things are going, and, we do love pictures...
