Feeding times - Introducing solids

So, they say that solids should be introduced mid morning, when baby is wide awake...

How would i time it then?

Say Alessandro wakes for the day with his first feed at 6... and eats every 4 hours, that means he eats at 10 again. But also has a nap before then again. When do i feed him?

Also, when do i give him breast again after his food? Do i start the 4hr countdown when he has his porridge, or continue from when i started at 6am?

Thanks for your help!