For "World Book Day," some parents enjoy purchasing clothing and customising them, while others choose to use what they already have at home, such as old clothes, to create something completely unique. I am the parent who will add a little personalization to the costumes, depending on time; if not, I will simply purchase the garments they require.
I have around two boxes worth of costumes and materials, and I try to use what I have before going out and purchasing another outfit to add to my already large collection. Over the years, I've seen that certain schools may choose themes such as superheroes, villains, and so on.
Having a theme might make things easier if you already have anything similar to the subject at home, and it also helps if you're unsure what to put your child in. Then there are times when you can wear whatever you want, like my daughter did for World Book Day this year, and we couldn't decide what to wear as a costume, so she chose Jessie from Toy Story, who is a rough-and-tumble cowgirl doll with a passion for yodelling, as well as an incredibly optimistic member of Andy's toy gang.
It might be tough to keep track of all of your child's school events. Especially if you have children in various schools. For us, World Book Day doesn't finish at school; I prefer the kids to come home and spend some time reading together and discussing what they've read. "Reading is gold dust," I tell my kids, since you can use your imagination to go on a journey with it, but movies can only carry your mind so far, right?