Sprog's best friend was turning 5. When I suggested a Batman cape for Friend, Sprog said "No Mummy, a Batman costume". Admittedly I had just finished his Catboy costume at the time.
The basic costume is the same as the ones I made for Sprog and Widget. I cut an approximate shape out for the ears, and sewed around the two longs edges. After turning them inside out I stuffed them with some of the pillow that had been killed by the cat, then topstitched about 1cm in from the edges. The combination of stuffing and topstitching held the ears nice and stiff. These I stitched to the side of the hood, using a large square at the bottom of each ear.
Both Batman logos I traced from images I found online, The grey for his tummy was edge stitched in black at all levels. The yellow on the back was edge stiched around the bat in black and around the oval in yellow.
The cape was a repeat of the superkid cape I did for another party. Put the two together and you have a cool present. Give that present and you have a very happy 5-year-old.