Guide to Installing The Photoshop Plugin
Make sure that the version of Photoshop is not less than 23.3.0 (you can check this in the Photoshop "About" menu), which corresponds to Photoshop 2022.
Locate the installation directory of Photoshop and move the extracted folder
picpik_ps_plugin_lastest into the "Plug-ins" directory. If there is an older version of the plugin, you can overwrite it.
Open the Photoshop's "Extensions" menu and select the Picpik plugin. If the panel appears blank, you can try clicking the "Reload Plugin" option in the upper-right corner of the menu.