Stating your opinion again in another way.
Reminding your reader of your arguments.
Add a call to action or a rhetorical question.
Sentence starters for your conclusion:
To conclude…
We’d all be better off if...
To sum up…
Without a doubt...
One thing I know for certain is...
It is easy to see...
As you can see...
Undoubtedly...
The reasons are obvious...
In conclusion...