How do you download pictures to dsi

Well first you have to buy a sd card for it,(i bought mine at target). Next you have to put your sd card in your computer, or if your computer doesnt have a sd card slot buy a sd card reader at radioshack,(mine was 13$). Then find the file your sd card is in. Then find a pic you want to put on your sd card and drag the pic to the sd card file. Then put your sd card into your dsi