You can trace through a debugging session by stepping into or over code or running until a breakpoint is encountered. These commands are available from the Debug menu or via keyboard shortcuts.

Step Into
When you hit a breakpoint, press F11 to trace into any methods called by the current code (Step Into).
Step Over
When you hit a breakpoint, press F10 to continue tracing through the current block of code without stepping into any methods which are called (Step Over).
Step Out
When you hit a breakpoint, press SHIFT+F11 to step out of the current method and continue tracing from the next line of the calling routine. (Step Out).
Run To Breakpoint
Press F5 to continue running the program until a breakpoint is met.
Run To Cursor
When you hit a breakpoint, you may select a line of code after that breakpoint and right-click to pop up a menu then select 'Run To Cursor'. The program will continue running until it encounters the selected line.
Stop Debugging
Press SHIFT+F5 to stop debugging.
See Also
Debugging
The Debugger