There's a couple things I do to try to save money on my writing: (1) buy reconditioned ink cartridges from Wallgreen's for $20 instead of new cartridges for $30; (2) save the paper and use the other side rather than throwing it out after just using one side.
Right now, I'm editing Tommy's Exodus, a novel, and if I'm wasteful the costs add up. Although, I do everything myself, including the covers, there is still expenses. If I watch these unnecessary expenses, It puts me a little closer to breaking even for the year.