@Jonpil - Are you asking about creating a segment for the climb or something different?  If you are referring to a segment, then those are created by users like you and me.  Once you complete and activity, you can open the activity on the website version of Strava and then look at the segments list.  At the bottom of the list there is a button that says "Create a new segment".  Click that and follow the directions to create your desired segment.  

When I first saw the title of the post, I feared Jonpil actually wanted to spray paint a line on the pavement for the start/stop of the segment.  I would not recommend that, It would raise the ire of the local authorities.  You'll have to use "live segments" on your bike computer to duplicate that.