(2) Save every half hour
(3)Alternate between the 3 save slots every half hour
(4) Use the quicksave function once a day as a "good save" a save that you know has no problems such as not being able to fast travel or something really game breaking has happened.
If you play for a day and find something game breaking and you cant recover it within the last 3 manual saves you always have the quicksave, even if it is from the day before its better than losing the entire playthrough.
What does this do?
It stops game breaking bugs and glitches from staying in your game and your save file. Would you rather lose 1 hour at most or 40 plus hours of gameplay?
Offtopic - buy and install a SSHD for your playstation 4. Youtube or google it. It will make a world of difference for fallout 4, other games and your system itself. No lag, no fps drop, fast loading speeds.