In the second aliyah, Moshe gives over G-d's choice of the skilled craftsmen to do the actual work, as we learned in last week's parsha. They are Betzalel and Oholiav as his assistant. They start construction, and the people continued donating generously, until the craftsmen report to Moshe that they had more than enough material for the building.
Moshe then proclaims throughout the camp for people to cease giving for this purpose, as there is enough material. The craftsmen continue building the Mishkan with the material previously donated, and build the Mishkan according to the instruction Moshe heard on Mt. Sinai.