You first need to find an area to place the structure on. In general, you need an open area that is relatively flat and large enough for the number of lots that the structure uses. Placement restrictions depend on the type of structure; however, you can't place a structure in or near a static city or too close to another structure or static spawn point for creatures or NPCs.
Once you are in the general area, generate the structure (the Use option on the deed's radial menu). You will get a face-down map of the area around your character, oriented with north up. You use the mouse to position and place the structure:
- Move the cursor to move the lot footprint of the structure. If the footprint is green, you are allowed to place in that particular spot; if the footprint is red, you have to choose a different location (yellow areas have non-terrain restrictions).
- Right-click to rotate the structure 90 degrees clockwise.
- Left-click when the highlight is green to place the structure in that location.
After placing the structure, don't forget to check it's status to be sure it has enough credits to pay for it's hourly maintenance fee.