Give Insertion Point:
Select the insertion point of the new symbol using any of the snaps and input options. This is the point by which the symbol will be attached to the cursor when it is inserted onto a drawing. Once selected the program prompts for symbol name via the following dialog box.
Type in the new symbol name and click OK. Alternatively you can redefine an existing symbol by selecting it from the drop down list and the system will prompt to confirm that you wish to overwrite the existing version.