I have to start with 'Handbook to Life in Ancient Rome' by Adkins and Adkins. I don't think it has left my desk in at least three years. It has basic details on just about every topic imaginable (Travel and Trade, Towns and Countryside to name two) and each section comes complete with a detailed glossary for further reading. Essential.
'Life and Leisure in Ancient Rome' by JPVD Balsdon kicks off with a description of 'the Roman day' then examines 'The Year', 'Family Life', 'Work and Leisure' and so on. Very concise, readable and engaging.
'Everyday Life in Ancient Rome' by Lionel Casson is a short but informative book and especially strong on life for 'A Roman Gentleman'.
'Daily Life in Ancient Rome' by Jerome Carcopino is an older, more academic text and is divided into two parts: 'The Physical and Moral Background' and 'The Day's Routine'. Both are exceptionally detailed.
Much more modern is Robert Knapp's brilliant 'Invisible Romans' which does a tremendous job of analysing the lives of 'ordinary' folk using the often limited evidence available.