How did Israel know when to move in the wilderness after the tabernacle was built?
After the tabernacle was finished, the Shekinah glory came down upon it. Whenever that glory lifted and moved, Israel took down the tabernacle and followed it. The movement of the glory signaled when they were to break camp and journey, guiding them through the wilderness.
Les explains that after God gave Moses the instructions for building the tabernacle, Israel accomplished all that while still in the wilderness of Sinai. As the tabernacle was finished, the Shekinah glory came down upon it. Then every time the glory lifted and moved, they took down the tabernacle and followed it. This was part of the giving of the Law, and they carried it on after the 40 years of wilderness into the Promised Land.