Broadly speaking, a sutta practice is a regular habit of interacting directly with the suttas in a way that lifts the heart and brings us to faith in the Blessed One, his Dhamma, and his Sangha of enlightened disciples.
In practical terms, this may be done by reading daily from a text, be it a traditional collection, or an anthology of suttas around a particular theme. The emphasis is placed on what is understood and taking that to heart. We approach the text as a sick person would seeking medicine, with the Blessed One as our doctor.
We practice with the suttas not to collect knowledge, but to gather the tools the Blessed One has personally given to us to overcome our hindrances and defilements.