[header] How to have a black widow as a pet [title] Find a container that is impossible to escape from. [step] Tea jars, jam jars, and any other jars are great because the lid is screwed on, and no spider can escape from that unless they've been working out. [title] Put a little vaseline or something slippery around the top ring of the jar. 
[step] This will prevent your widow from trying to climb out. [title] Before you go catching your spider, you may want to research if it is legal in the area you are in.