I don’t know how the sim card slot is in your Nokia . With my Nokia N96, you open a little cover to place the card on the contacts and then close and lock the cover. So what I did was to copy all my contacts from the sim of my Nokia onto the Nokia phone mem. Then, I fiddle around to place the micro sim on the contacts in the Nokia and then close and lock the cover. So I could copy all my contacts from the Nokia phone to the micro sim and then put the sim back in the iphone 4.
It could be easier if you buy a cheap adapter for the micro sim on ebay, which turns it into a normal sim size.