First, open your tree on Ancestry.com. Click the Invite button in the top right. Or, click the button above More on the left toolbar, then select Invite.
Under the Invite link option, select 'Guest' for the role.
Make sure to allow viewing of living people.
Finally, click the "Copy link" button.
Once the link has been copied, go ahead and paste the copied link into your email to MyCanvas, and we'll be happy to take a look!