Different Stages
Stage 0:
You set up your Node, but didn’t provide stake for it yet. At this point your Node is not part of the network.
Stage 1:
After staking, the Node moves to Stage 1. The Node joins the other Stage 1 Nodes, all waiting to be randomly selected.
Stage 2:
On random selection, the Node moves to Stage 2. The Node joins the other Stage 2 Nodes, all getting ready to create blocks.
Stage 3:
When a new Epoch starts, the Stage 2 Nodes will be assigned to a shard to create blocks for the next ~4 hours (1 Epoch), and earn the corresponding block rewards.
Stage 4:
After one Epoch of creating blocks, the Node is moved to Stage 3 for another Epoch of creating blocks, or moved to Stage 1 waiting to be selected.
Further Reading