There are a few options. One, if your .gpx file has numbered markers already, you can use the GPS Map Design Center to upload the file for overlay on a large-format, custom topo or aerial. Here’s a link to the GPS Map Design Center: http://www.mytopo.com/gpx/gpx1.cfm
If you need to label the markers, you’ll need annotation tools to do that. You can use the MyTopo Map Pass to upload the markers, then the add text label tool to denote the marker numbers..
These are the two easiest ways to accomplish your goals. Our cartographers would be glad to provide further assistance. Please do not hesitate to give us a call.