Instructions or tutorials on making door wreaths are available via BuzzFeed.com, GoodHousekeeping.com, TipJunkie.com and Save-on-Crafts.com. In some cases, the sites have compilations of different types of door wreaths from other sources. Links to the tutorials may be on the source websites.
BuzzFeed's "50 Unexpected Wreaths You Can Make out of Anything" showcases door wreaths made of crayons, gift bows, gift boxes, marshmallows and cooking herbs. The gift box wreath link takes you to Blog.ConsumerCrafts.com that has step-by-step instructions accompanied by photos.
Good Housekeeping's article focuses on springtime wreaths, each of which has a tutorial, such as one for a tulip wreath. TipJunkie.com offers 88 wreath ideas, including a patriotic stars-and-stripes version made from a foam core and small squares of felt.
For more traditional, Christmas-style wreaths, see the examples at Save-on-Crafts.com. A general wreath-making tutorial is available just below the pictures.