Mast set up

Hello everyone,
I'm new to the forum and recently (a few months ago) bought a DS1 that required some work / repairs. I finally have her ready to sail and I have no idea how to get the sail in without it seemingly being ready to fall over. Mine has a solid mast that has to be put through the cabin roof to stand it up. I saw a youtube video with a way to do it but it was still extremely unstable trying to get it in. I've a linked the video below. But I'm looking for any ideas on how to get the mast up.
https://www.youtube.com/watch?v=39KBRZwOhDI
Thank you for any help!
I'm new to the forum and recently (a few months ago) bought a DS1 that required some work / repairs. I finally have her ready to sail and I have no idea how to get the sail in without it seemingly being ready to fall over. Mine has a solid mast that has to be put through the cabin roof to stand it up. I saw a youtube video with a way to do it but it was still extremely unstable trying to get it in. I've a linked the video below. But I'm looking for any ideas on how to get the mast up.
https://www.youtube.com/watch?v=39KBRZwOhDI
Thank you for any help!