Newspaper is fine but not the glossy or stuff. Don't use soil. For a bed use damp coir or damp shredded paper then lay food scraps over it and just keep adding to it coffee grounds and tea leaves are good. a little garden lime every so often to keep it sweet and let them have fun. Try not to let it get too wet as that will encourage them to escape. As stated keep in a cool place in summer and they will go forth and multiply.....or come in 5th
Pete