If you are looking to issue new shares within a previously existing security, go to the security page, and then click Actions > Issue Shares on the right side. This will bring you back to the spreadsheet view where you can type in information directly into the sheet.
Enter all the pertinent information on the correct tab. For instance, if you are issuing options, go to the “Option Grants” tab at the bottom. Don’t forget to check the additional columns to see if there is anything else you wish to enter.
Alternatively, you can open the left nav-bar, and under “Cap Table”, click on “Spreadsheet”