Setting up ICloud Photos

Hello,

I own an Iphone 7 and a Macbook Pro. I recently decided to start setting up Icloud to make everything Sync and Backup. I spent a lot of time recently going through photos on my Macbook and deleting ones I did not want and just yesterday I had all of the remaining photos uploaded into Icloud.

On my cell phone, I still have many of those photos that I deleted off of my Mac. My Iphone is not yet connected to Icloud. How do I set up Icloud on my phone without getting all of these bad photos uploaded and mixed with my nicely organized photos currently there.

My current plan: Delete all photos from my phone while it is disconnected from Icloud. Then set up Icloud for photos. Then download all the good photos from Icloud back onto my phone?

Thanks!