Covering with card

Covering with card is a good idea, it wiill help suppress weeds and will also break down and help the soil over a long time - or if it is just soggy, come spring tear it up and add it to the compost heap. You might possibly get away with some of the green manures, depends where you are probably, (and I can't see your location now that I am typing), my field beans have only just germinated.
 You could definitely improve the soil where you  are going to plant beans or marrows by digging a big hole in the beds and filling them with kitchen waste, allotment clearings (not perennial weed roots), grass clippings and cardboard or shredded paper, cover it over with soil you dug out and you should have much improved soil come planting time.
Most people have had poor carrot crops this year and many people have had poor potato crops because of blight. The bad weather has meant that many growers have had much worse years than usual, so your soil may not be in as bad condition as you think

There is still time... If you are able to collect manure there is some available locally to you:

http://groups.freecycle.org/aylesbury_freecycle/posts/21762223

If not, you could ask if they will deliver for a small payment... or do a google search for other manure supplies near you.

Remember not to manure where carrots are to go otherwise they will fork.

I have decided to weed, dig and then cover with card (half my plot) until this time next year when I hopefully will get some manure!! Does this sound a good idea to you guys! Anything else I can do to help the soil in preparation!! Thanks in advance!! G

Do you mean to leave the plot for a complete year under the card, just because you haven't got any manure?

I agree with leaving it until the spring, but it seems a terrible waste to leave it over the growing season - even if your committee / council allowed you to go a year without any cultivation (you wouldn't get away with that on our site).

Manure is great but it is not the be all and end all.  It improves soil structure but does not add particular quantities of nutrients.  You would not add manure where you plan to grow carrots or parsnips the following year anyway.

Plan to grow stuff next season and read up on fertilisers.

Like Yorkie, I was puzzled by your plans.  I think leaving your plot empty for so long is a waste.  

If you can't get hold of manure, simply buy some pelleted chicken manure or blood, fish and bone (Poundland do it) to feed your soil before planting (not now).  You could even get some overwintering onions and garlic in now (plant through layers of wet newspaper if you are worried about weeds appearing in between).

Covering with soil would help stop weed growth, but there could be loads of reasons why your root crops didn't do very well - carrots for example, don't need loads of nutrients, but do need a good, sandy soil to stop them bolting.  Potatoes were a disaster for almost everyone this year due to the wet conditions.  

Clay is usually pretty fertile, manure is great but adding grass clippings will help with the soil structure, but you can also add some fine grit or sand to help drainage.  As has also been suggested, build a compost heap and start making your own as this will also help to improve the soil structure.  Come spring, if you sow your carrot or parsnip seed into a drill the depth of your spade filled with compost, this will help prevent them bolting.

If you are getting manure on Friday, yes by all means go ahead with your plan although be prepared as usually manure contains weed seed too, but at least if you clear these weeds in spring, they won't be deep rooted.  If you go with my suggestion of onions and garlic, don't bother manuring the soil in advance as they aren't keen on freshly manured soil.  Brassicas and legumes will love the manure when the time comes.

OK, no worries gathsman, I misunderstood your plans.  This is the right time of year to be prepping your soil so you are ready for the new growing season, definitely.

Awesome, now that sounds like my type if allotmenteering! I will post an update tomorrow when I take delivery of my manure!!