Use catch words that people would search for. Use headings and pictures that make your item stand out from others.
If you have a popular item you need to find creative ways to advertise your it and also use differnt selling tecniques from the other sellers.
You could start your auction with a lower starting price or have a buy now price so people dont have to wait for you item to end.
Have as many pitures as you can as to show the quality of your product.
And above all accurately describe your item so that if you were buying it you would be happy with your purchase.
Do a little bit a research on the item you want to buy. Check authenticity if you are buying things like collectors items.
Ask questions about your item before you bid.
Keep track of the items you are interested in by placing them in your watchlist.
If you really want to win the auction you may be better of placing a proxy bid which means, you put in the maximum you would like to pay and then you don't need to watch it all the way to the end.
Personally I like to sit and watch but there have been times when I have forgotten or haven't been home so I miss out.
See how many listings there are for the item you want and watch for what the others go for to get a rough idea of prices.
Check out the sellers ebay rating and coments made by other people who have dealt with seller. I beleive this is the best way to monitor you sellers performance.
Check postage rates to your destination and see if you can combine postage if you happen to buy more items from the same seller.
Above all honesty is the key to buying. You need to trust them to sell the item they have described and send it and they need to be able to trust that you will pay for the item you have purchased.
I have had an enoyable time with ebay. Not only buying and selling but also talking with people i would not have met in everday life.
I hope you are enjoying your time on ebay also.