Planning is vital – it’s a lot easier to fix cables & pipes before you’ve plastered; and it’s a lot easier to know what pipes and cables to put where if you and your partner have agreed where appliances will go. Really “childish” stuff like making a plan on the kitchen floor of where appliances, cupboards, etc will go is essential unless you can all clearly visualize how you will use the kitchen to cook/entertain as a family. Defo say it’s worth living with detailed layouts/plans for a few days before you start work; as this lets you ask questions, like where will the cat go, will the dog be alright there, can I get the bikes through there, etc, etc. It’s also worth looking at more modern products to see how they compare with old-fashioned labour-intensive methods that your grandad might have used. Worth looking through the Tool Hire catalogue to see what kit they can hire out too; as half-a day with a specialist electrical tool can save you days of effort using the wrong one. Finally, wear safety goggles – I’ve seen far too many people with drills, planers, routers and even angle grinders taking stupid risks with their eyes.
