Hi Drop, here are a few pointers!
Start things on a Sunday so the end on a sunday, you get a better audience then.
weigh the packages before you make the listing. I buy my jiffy bags from the £1 shop, so you get say 5 for a quid. Nobody likes been ripped off on postage, but I always add on 50p, 20p for the jiffy and 30p to cover paypal.
If you're wondering about how to weigh the items, you can pick up small digital ones from Argos for around £22. That way you don't loose out, or get angry complaints from buyers! Me and DH have sold over £400 worth of ebay stuff in one year (just stuff we don't need) so the £22 scales were a good investment
Pictures! As many as you can, and learn how to upload them on to your web space if you have it!
Don't start an item at £1.00, it'll cost you 20p, start it a 99p and it'll save you 5p per listing!
Nicely worded adverts that have been taken time over get good results I agree with everyone else on that, esp the spelling!
Good luck with the selling!