How do you retract a bid?

[MincePiesAndBaileys]

I have done it before but a long long time ago.... dont want to risk not being outbid, basically I bid on an item, but then saw another item later which was cheaper on Buy it Now....there are nearly 3 days left on the auction...

Technically you can't - you have to email them and ask them to cancel your bid.

The Bid retraction form is here: offer.ebay.co.uk/ws/eBayISAPI.dll?RetractBidShow&guest=1 BUT these are the conditions:

It is ONLY OK to retract a bid if...,

You accidentally enter a wrong bid amount (for example, you bid £99.50 instead of £9.95). If this occurs, re-enter the correct bid amount immediately.
The description of an item you have bid on has changed significantly.
You cannot reach the seller. This means that you have tried calling the seller and the seller's phone number doesn't work, or you have tried emailing the seller and it comes back undeliverable.