*Brigadoon - think the very first thing for you to do is to start to collect ideas as to what sort of property you will wish to move to and where.
Start making out your own lists - WHat is absolutely necessary, what you would like, what you can cope without. You will probably change these priorities as you actually start to look at properties.
Then, with this in mind (and also some idea of how much you can afford to pay), look on line at properties. Can get a good idea as most have room maps, and roomszes.and many have video films of those properties. Do remember that videos and photos are taken, often with special lens to make rooms look much bigger than they actually are.
You may also need to have some idea as to the real price your existing house is likely to get on the market. Estate Agents will almost definitely give you an inflated price, so, do knock off at least ten percent of what they say. Also note the other costs involved, Solicitor fees, estate agents fees, removal cost, and usually a move involves quite a lot of new furniture, etc. etc. Many people who move find that the first year in a new property can easily involve twenty to thirty grand of costs . So be realistic.
Location is so important. Work out what you require in your new location, shops, parks, cinemas, public transport, hospital (east to get to), Doctor, pharmacist, etc.etc.
Having done all this over some months, and also a good look at your existing home to think about what may require doing before putting on market (not just de-cluttering, but decorating, repairs, etc.), then you can think about how you will go about all of this.