Once the pavers were placed, they filled put down a layer of mulch between them all.
After that, they poured bags of landscaping rock on top of the mulch, to fill in the gaps between the pavers.
Also they sprayed it all down with a little bit of water to help get rid of all of the dust and let the stones start to settle. Once it rains a few times and everything settles a little more, they may have to add a few more bags of stones around the pavers to help keep them in place.