That's exposing some of roots as well as settling the soil, a mixture of soil from the pot and the surrounding lawn, into the bottom of the hole so that they'll really congeal around the root. Then once you have a little water in there, you want to backfill the rest of the hole up to the point where the soil is level with the surrounding ground. If you have a little extra, that's OK, you can always spread it out somewhere else.
Once you have a reasonable amount of soil into the hole, come back in here with your water again and really spray it down. Get as much water as possible into the hole. Once you have a decent amount of water in there, you can just give it a little shake, shimmy, to get some of the air out. Then you'll want to come in with your rake and pull the remaining soil without too much mulch in it back onto the top to bring it up, finally leveling that off. Then give it a little more water. You can really see how wet I'm making that. That's really what the plant likes when you initially start it. Don't worry about giving it too much water because you're not going to water it again for a couple of weeks. You're going to let it set and heal in there.
Then as a final, just pull in some of your mulch back in around the plant. You can finish that off aesthetically. What you want to make sure that you do after the plant is planted, you've got plenty of water in that hole, so don't water it again for another couple of weeks. Let it sort of dry out and heal in. You also don't want to be pruning the shrub after you plant it because, contrary to what a lot of people have thought for years, pruning a shrub ruins it and keeps it from really establishing itself in the ground.
Lastly, you don't want to fertilize this shrub until it's well established and its roots are healed in the soil. That might be as much as six months.
Those are the keys to planting a shrub. Make sure you don't plant it too deeply. Rough up the root ball so the roots will move out of this soil. Use plenty of water. Then, in the end, don't prune or fertilize. That's my tips for planting shrubs.