My first paragraph would be 1-2 sentences that would probably introduce my claim. For example:
"I believe that cats are better than dogs because cats have a lot of qualities that a person may find admirable."
My next paragraph would support my claim by providing evidence. Another example:
"It has been proven that cats can help to lower stress or anxiety, because they are soothing and trigger calming chemicals in the body."
My third paragraph would mention the side I'm arguing against, but I would prove why it (the opposing claim) is wrong. For example:
"Unlike dogs, cats lock themselves clean which is less work for the owner."
And finally, my last paragraph would be a conclusion, which would involve you restating some points you mad previously. Example:
"In short, cats are better than dogs because they can lick themselves clean..."
Hope this helps!