7. Measure the volume of the hydrogen gas produced by the reaction.
Another thing, how exactly is this done? If this the final aim? Which of the above steps do you think compromise this measurement?
On this forum, we like to see a little effort from the poster, then we offer hints or help with some small problems. You haven't made any effort, and you're not asking for hints, just for us to do it for you. Please don't think that copying the procedure from your text counts as effort, especially hen you've left crucial steps out.