Long distance

So I recently started seeing an older man (age doesn’t worry me) and not long after we started dating he got a job offer 6hrs away! Now I’m not one to say don’t take it and stay with me, but I am a bit upset. He didn’t like the previous company he worked for and will be earning more at this new job, and to me his happiness is everything. We went on a road trip and discussed us and he asked us to be official which I was happy to do with long distance. I’m really falling for this man and I want to do everything I can to make this work. Any advice for long distance relationships?