I always start with an "easy" room, like the bathroom, or a hall cupboard. Makes you feel like you have achieved something.
My other stronly recommended tip, if you have a car or access to borrow/hire one, is let the removals men take the big heavy stuff and general boxes, bu pack your small fragile or valuable/electrical items in your car, along with a box of any bits and pieces you will want easy and immediate access to, i,e a kettle, tea, coffee, sugar, plates,cutlery, duvet, sheet, pillow.
In my exerience of moving, fragile and electrical stuff is the most likely to "GO MISSING", or get broken, so avoid letting burly movers/strangers near it!