Step 1: You will need...
1. Large enough ziploc (or similar) plastic bag.
2. DSLR camera with hooded lens;
3. Pair of scisors;
4. And some good quality gaffers tape.
Make sure that the gaffers tape you're using is not leaving sticky residue when removed. That's the reason why those tapes sold at B&H Photo are so much more expensive that stuff from your local utility store.