worship God is adoring Him, doing what He asks and declaring Him to be far superior to us.
it's thinking of Him first every day, praising Him in every happy moment and asking for His help when we are in need.
venerating the saints is thanking God for their lives, congratulating them on arriving ahead of us, asking them to pray to God for Him to forgive our sins and us asking God to help us learn from their example (and in some cases, also from their mistakes).
God is our Father, creator and saviour.
the saints are our big brothers/sisters, colleagues and role models.