Faster experience
First, find a Boss that gives a lot of experience points. Before fighting it, save the game. After you defeat the Boss, create another save file and save the game on that file. Load the first file that you saved, then import your character from the second saved game file. Fight the Boss again, then overwrite the second file. Repeat the process until the experience points from the Boss is not longer satisfactory. Remember to not overwrite your first save file.