Open the event and click GPS.
Select your format and file, click OK. If you use Garmin hst file, you may need to delete all older event from your .hst file with text editor.
If you use FRWD, you need to write out English language version of text export (language versions has differences).
Select your class/course and zoom out until you can see whole route and tree blue dots.
Drag three blue dots to the right locations and try to calibrate your route on map as well as you can. When you feel like you can not do any better, click OK button.
Then use "add points" tool to add more blue dots. First add them, then click the tool off and drag dots. Use controls, sharp path turns etc. You can delete blue dots with "delete points" tool if you need to.
Map and gps accuracy is never perfect. Here is example how you can move your route a bit to place it on the path you ran.
Yet an other before and after example.
When you have finished and your route look's ok, select your name from the list (or write your name), type some comments and push the "Save route" -button. Your gps route will appear at the bottom of the list. Note! You can also draw your route, you may learn something if you first draw your route and then upload your gps route and compare those two routes.