Best way is the cloud. PC or Mac though? For PC once you plug in the phone with a micro USB cable or the charging cable the PC should see it. The phone should come up under my computer and allow you to open the phones files. It should have a folder named pictures which you can then drag and drop photos to your phone or from your phone.
If you use a Mac, I honestly have no clue. I have never used a Mac desktop or laptop.
Posted via Galaxy Note 3