Using Dynamic Tool Selection
Dynamic tool selection allows for quickly switching to a different tool as long as the shortcut key is held down. Once the shortcut key is released the previous tool will be selected again. To select a tool with a shortcut key in non-dyanmic mode just press the key quickly once normally. Here is an example in usage in dynamic mode..
Step 2: Press and Hold the Shortcut Key for the Rectangle Tool

- Notice the Shortcut Key for the Rectangle tool is "U".
- While the U shortcut key is pressed the Rectangle tool will be active.