It is customary (although not mandatory) to create an activation report of your trip. This can take many forms, from words to pictures, a human-readable log of your contacts, a QSO map, or a video perhaps. Anything is cool, really, and you are encouraged to be creative.
These records are often posted on the SOTA Reflector, although they can be posted at their own location too. The reports are meant to help you remember your day (what worked and what didn’t) as well as focusing on the other reason we do this: the scenery and the walk.
So, plenty of photos of your setup and operating, but also plenty of photos of the scenery and anything interesting that you encounter. When writing up your reports you can be as expressive as you'd like to be. Keep it simple or turn into Wordsworth, whatever. It's your report and your documentation of the day. People do like to read the longer, narrative reports and they do quite well on the SOTA Reflector.
For making maps you could use many tools. Google Maps and ArcGIS are just two, and both will allow you to throw some dots on a map and label them. An interactive, clickable map would be extremely cool vs an image. Seeing how far and wide your signals have gone is always nice, and a map allows you to achieve that and show off a little bit.
Below are some examples of activation reports in a variety of forms.