Cut the EMT conduit into six five-foot lengths. Use a pipe cutter for this. The five-foot lengths will form the cross-pieces, or joists of the structure's roof.
Cut six more five-foot lengths of EMT conduit for the sides.
Cut two more five-foot lengths of EMT conduit for the peak of the roof.
Cut the EMT conduit into six 6-foot lengths for the poles on the sides, and three 12.5-foot lengths for the middle poles.
Begin with the middle of the structure. Fit four of the 5-foot lengths into the middle fitting.
Fit the side fittings onto the ends of the EMT conduit, extending from the middle fitting.
Fit 5-foot lengths into the side fittings and connect them with the corner fittings.
Drape the tarp over the roof and secure it in place with string. Lash the corners and center of the tarp to the EMT conduit.
Lift the roof of the structure -- you will need two or more people as assistants -- and fit the posts into all the fittings. Put the foot fittings onto the bottom of all of the poles.