First google a quick review of the basic learning styles (auditory, visual, or kinesthetic) and try to determine which type(s) of learning your daughter does best.
If she's auditory, then reviewing a few words a day with plenty of vocal repetition will probably serve her best. Making up tunes to help memorize spellings can be very helpful.
If she's visual, supplying pictures with each word (she can even cut and paste from magazines), will help, as will posting the word(s) of the day on cards around the house so she will see them frequently.
If she's kinesthetic, then ask her to come up with some funny gesture or dance move as you read each word. Repeat gestures / words, switching which comes first. Actually writing the words with large arm movements on a big sheet of paper or a blackboard will also help get them into her memory better.
There are plenty of additional suggestions for different learning styles online. As Susan (S H) says, just a few words a day are plenty. Overload won't help.