The best way is to go by Train for day trip . Southern is doing a special offer as following from their website.
^You can now save a massive 50% when travelling Off-Peak, simply by booking your ticket online. And children can travel for only 50p each.
Our half price offer is now available on Off-Peak tickets for a limited period only – Special Offer ends 11th April "
Many thanks will check out the website
In the absence of special promotional fares at the time you want to travel, the general rule is to travel off-peak, that is after about 9.30. These can be bought on the day if you want to be flexible. Depending on where ou are staying you can leave from Victoria, London Bridge or St Pancras stations. Using the bus between London and Brighton takes a long time compared with the train.
<<omeone said that train travel was very expensive is this true? >>
No its rubbish, booked in advance you can do it for under £15 return.Edited: 24 March 2010, 17:06
Off peak times are after 9.30am and what in the afternoons?
<<<<Off peak times are after 9.30am and what in the afternoons?>>
The website says for each ticket if its off peak, anytime or a timed exact train (usually the cheapest) etc ojp.nationalrail.co.uk/en/s/planjourney/query
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