For those who haven't converted to the 32 mm shelf hole system or those who just prefer using the traditional 5/8"wide by 3/16" deep metal shelf standards, I suggest a time and labor saving technique.
You can add a jig to the front plate assembly of a Senco series L stapler (other brands may work equally well). This add- on jig locates the stapler so that the staples go through the two holes provided in the shelf standard. You use 1/2" staples. Senco's catalog number is LO
8 (18 gauge) other equal brands will probably work as well. IIRC the jig is not a catalog item but needs to be fabricated by your saw sharpening shop (or a machine shop). It takes two socket head cap screws to attach it to the front plate.
If your building a long wall of bookcases,this can save you some time.
JoeG