How about using wooden printing blocks to design a T-shirt? You will need to place the sponge mat (essential for creating a clear image) inside the t-shirt before you start. This will also prevent the fabric paint going through to the back of the shirt. Use the paints direct from the bottle as they are just the right consistency and will not bleed into the jersey fabric. 

Of course, there are many different methods of printing and you can use all sorts of everyday items. Look around your kitchen for example. Brushes, scourers, sponges, corks, in fact anything that will take paint, is suitable. And why not try fruit and vegetables?