Your UI is highly personal preference, so I won’t give any guide on how to set it up. In general, you want to set up something that lets you monitor your abilities, the encounter itself and your team members.
The general recommendation is to use the Weak Auras addon to track everything you need.
Retribution Paladin don’t have a lot of mandatory macros for PvE, as they’re mostly just mouseover macros to assist your team.
Final Reckoning Cursor Macro
Can save you some time as you don’t need to click your mouse to target the ability on the ground.
#showtooltip Final reckoning
/cast [@cursor] Final Reckoning
Lay on Hands Mouseover Macro
You can have a single button for Lay on Hands that will heal an ally under your cursor and if there is none - it will be cast on yourself.
#showtooltip Lay on Hands
/cast [@mouseover,help,nodead]Lay on Hands;Lay on Hands
Word of Glory Mouseover Macro
/cast [@mouseover,help,nodead]Word of Glory;Word of Glory
Blessing of Freedom Mouseover Macro
#showtooltip Blessing of Freedom
/cast [@mouseover,help,nodead]Blessing of Freedom;Blessing of Freedom
Blessing of Protection Mouseover Macro
#showtooltip Blessing of Protection
/cast [@mouseover,help,nodead]Blessing of Protection;Blessing of Protection
Cleanse Toxins Mouseover Macro
#showtooltip Cleanse Toxins
/cast [@mouseover,help,nodead]Cleanse Toxins;Cleanse Toxins
Divine Resonance Ticks
This WA makes your life easier when running the Divine Resonance talent. It helps a lot not to waste your judgment debuffs or holy power.
Divine Resonance Ticks WeakAura: https://wago.io/j2CII_Uuk