Ineffectual,
In addition to using the information already presented, you should do a
Super Search on benchmarking. Since the title of your node was "first time", I expect that you might run into some of the same problems I did my first time around. The two biggest things I will point out are:
Run your tests on an inactive system (single user mode with cron disabled if on *nix if possible)
If you are using external data, vary it. Comparing algorithms to split a strings will tend to give biased information if the input is not varied.
You might also want to check out http://www.perlfaq.com and http://www.perldoc.com for frequently asked questions on the best practices of profiling your code.
Cheers - L~R