A word can be easier to remember when it has more than one useful clue. You might see the spelling, hear the sound, say it, or read it in a short sentence.
Use only the clues that help. Audio can show pronunciation. An image can help with a concrete word. A sentence can show how grammar works. Too many clues can make a card hard to use.
Start with recognition when a word is new. Then move to recall by hiding the answer and producing it yourself. Keep each card focused on one small task.