A chain is only as strong as it's weakest link.  While you can do things to try and prevent Ransomware, it is best to take a proactive approach on how you will recover from a Ransomware attack.  Pretend that you are going to be hit with a Ransomware attack tomorrow.  What will you do today to prepare for the recovery?  I find that the best approach to an attack is to have a good off-site backup in place so you can just remove the infected computer and restore your files to the last restore point.

Having multiple full backups and doing incremental backups will help prevent your data from being lost.  At most, you will lose 24-hours of work if you do a nightly backup, none if you are doing the backups in the middle of the night and you figure out that you have an issue first thing in the morning.  It is a lot less expensive to recreate 24-hours of information than it is to pay the ransom to "maybe" get your files recovered.  Remember, these are the same dishonest people who encrypted your files in the first place.  They are under no obligation to honor their side of the bargain by giving you the encryption code.