received flat, fold them.
if your invitations included tissue paper, place that over the writing of your invitation. depending on the style of your invitation, the tissue paper will either lie on top of a non-folded invitation, or will go inside a folded invitation.
next, place the reception card on top of the tissue paper (again, either inside the card or on top of a non-folded invitation).
tuck the response card in the flap of the response envelope (not actually in the envelope) so the writing on the response card is facing out. this should then be placed on top of the reception card. if the invitation is a folded invitation, the top 