I have researched links to some DIY filters so I can experiment with some different film techniques. Here are some I found:
DIY Lights and Lens Filters – How to turn stockings into lens filters.
10 DIY photo filters to think outside the app – This link suggests to use lace as a DIY photo filter, I like this idea.
How to make camera filters and special effects – Another link demonstrating using lace and cling wrap.
Shoot hazy and ethereal photos using a sandwich bag and coloured markers – I really like this idea – excellent for my project.