This is an easy and safe way to give access to a web developer or tech volunteer to your domain. instead of giving them credentials to your domain registrar (godaddy, bigrock, etc) . Following steps are for GoDaddy. You could search how to do the same for other domain registrars. most have this feature.
Then go to “Delegate Access”
Choose the type of access you want to give. the one shown below is the safest and minimal (but you might want to give more access based on your requirement)