What is the best way to give other developers access to my droplet to help develop my site without having to give them my login details?

This question was answered by @sierracircle:

There are different ways to go about this. My preference:

#Create a new user, for example:

sudo adduser bob
sudo passwd bob
sudo mkdir /home/bob

#Create a group for people who will be working on your sites:

sudo addgroup webmasters

#add bob to webmasters:

sudo usermod -aG webmasters bob

#give your new group permissions on your website files:

sudo chown -R www-data:webmasters /var/www

and

sudo chmod -R 775 /var/www

#and finally make a link to your website folder in your new users home folder:

sudo ln -s /var/www /home/bob/

now your user can login with whatever password you created. There will be a link to the website folders They should have permissions enough to work on your site.

You can delete that user with:

sudo userdel bob
sudo rm -r /home/bob

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