Disclaimer: I didn’t map everything in the difference (like the lake was already mapped) but did add the tails and buildings.
Diff was generated using this tool: https://pierzen.dev.openstreetmap.org/hot/leaflet/OSM-Compare-before-after.html#16/41.9618/-73.7594
I used OSMand app on android to record my GPS while walking. There is a plugin called “trip recording” that you can use and it saves locally to your device. From there you can upload directly to OSM or send the gps trace to your computer and drag/drop it to the web interface. Here’s a nice video showing how to do it https://youtu.be/3FqSYXxMCIs