Regarding main/master. I think it's your choice. Main is the default branch when you create a gitlab repository (and salsa is a gitlab instance).

About the how part:

On salsa, goto Settings > Repository > Branch Defaults
and set 'upstream' as default branch

$ git checkout master
$ git branch -D main
$ git push origin :main
$ git branch -m main
$ git push origin :master
$ git push origin main

Set main as the default branch now


Oh, about that. goto Settings > Repository > Branch Defaults and make master default


cd /var/www/debian/pynpoint/
git clone git@salsa.debian.org:debian-astro-team/pynpoint.git
cd pynpoint

git checkout upstream;git checkout pristine-tar;git checkout master
#git status

gbp import-dsc ../pynpoint_0.6.2-1.dsc
gbp import-dsc ../pynpoint_0.6.3-1.dsc
gbp import-dsc --no-sign-tags ../pynpoint_0.8.1-1.dsc

#git status .
git push origin master upstream pristine-tar;git push --tags;git push -u origin --all

# for new repos
git push origin master upstream;git push --tags;git push -u origin --all

gbp import-dscs --debsnap wmweather+

13:45 < Myon> tarzeau: git push -u origin pristine-tar
13:46 < Myon> or git push -u origin --all
tig --all
gbp buildpackage -S --git-pristine-tar

pristine-tar commit ../pynpoint_0.8.3.orig.tar.gz

gbp clone https://salsa.debian.org/science-team/meshlab.git` followed by `cd meshlab; gbp export-orig

alias.master2main=!git branch -m main && git branch -u origin/main