Clearing the ArcMap Cache is a standard practice that is known to improve the quality and performance of the GIS application.
- Open the tools menu at the top screen and select "ArcMap Options"
- From there, select the tab "Display Cache"
- From this menu click the "Clear Cache" button.
This should never have more than 500mb at a time for best performance.
ArcMap allows for you to have addon's to assist with various functions.
You are allowed to have up to 30 addon's selected at a time, but it is recommended by ESRi that you only have enabled that which you need for a various project.
By having 30 addon's installed and active at one time, it severely slows down the application. If you only need 3 addon's for a given project, then it is recommended to only have those 3 enabled for the duration of the time spent on that project.
You may select the toolbars from the addon's menu within the ArcMap Options tab.
It is also recommended that when mapping/connecting to file locations, that you select the subdirectory that the project is being stored.
If you select multiple drives to map to, or the root of multiple drives, then you will experience increased indexing slowness as the application scans each connected drive (through ArcMap) before making any changes.