Use Edit->Preferences->General to open the Edit Preferences dialog on the General tab.
Notice the list of tabs down the left side. Turn on Use Shift Key for Tool Switch
Select the Saving Files tab.
Increase the Recent File list to 20.
On the Performance tab, increase Memory Usage to 60% depending on your OS, and the memory available. Also put the scratch disk on a separate drive from your paging drive if possible. (Paging drive should be available wherever you can find operating system info.)
On Display/Cursors tab, set Painting Cursors to Full Size Brush Tip.
On the Grid tab, set Spacing for Major Grid Lines to pixels, Gridline every 100, and 10 subdivisions.
Ok these changes.