Plugin Deveopment: Precautions I need to take to avoid issues

I am entering to the exciting field of WordPress plugin development.

Often I see that installing of one plugin causes issues to other plugins installed or sometimes it breaks the entire site. I know it is difficult to have a definite set of rules to avoid such issues.

But from your experience/knowledge can you share with me what precautions I can take while developing the plugin to avoid such conflicts?

Thanks in Advance.