For many people the hardest part will be sending out the email where they commit themselves to a topic and a date to present. Choose a topic you know well, or a problem you have recently solved.
Once you've picked your topic email the Toronto Perl Mongers list and let the list know you are interested in giving a talk. Be sure to include the topic of your presentation in the email. Usually it will be accepted quickly by the group and someone will update the web page, making it “official”. Don't back out, you can do this!
Email the TPM list at <tpm@to.pm.org>.
In the email include your topic and when you are able to present.
As much as possible this presentation will try to give you practical advice. Choose a topic now that is of interest to you, and that is relevant to the rest of the group.