Here is a good warm up drill if you only have 1 goalie. It is similar to the origial three lane shooting drill but adapted to shoot on one net. Set up the players along the boards at the blue line. The coach or another player has all the pucks just inside the other blue line.
On the whistle P1 skates along the boards and swings to the other side of the ice to receive a pass from the coach. P1 stays on that side of the ice and shoots from about the top of the circles. When the pass is made P2 skates along the boards to the red line and then swings into center ice to receive a pass from the coach. P2 stays in the middle of the ice and shoots from about the top of the circles. Once the pass to P2 is made P3 begins. P3 skates up to the far blue line and opens up (inside to outside) to receive a pass from the coach. P3 stays on the near side of the ice and takes a shot from the top of the circles. It is also nice to allow P3 to go in for a close range shot or deque so the goalies get two long shots and a close range shot.
After their shots, players line up on the other side of the ice.