1 plan your ride on map my ride . com
2 go to the route tab on map my ride . com
3 save to garmin/crs
4 set speed or pace
5 download crs file to wherever you want on your computer (upload to computer as crs NOT tcx)
6 upload the file into Garmin Training Center.... File... import
7 in GTC find the courses folder on the left look inside folder and find downloaded ride
8 plug garmin 500 into computer (mine takes a few seconds to find the 500)
9 select course to be uploaded to garmin 500
10 select device on GTC software and then select send to device
11 eject garmin 500 from computer
12 power up garmin 500
13 hold page/menu button to select training
14 select courses and find the course you just uploaded....
15 select do course
16 go ride....
It's actually a little easier than that.
1st 5 steps are the same, but instead of uploading to GTC, you can upload directly to the garmin. Just copy the .crs file to the new files folder on the garmin. Next time you turn on the garmin it will convert the .crs file and you will have a new course saved.