2. Do not give false Information
Most times, applicants give false information in the bid to present themselves in a better light. They believe that the truth could limit the chances of their visa being approved, forgetting that the applications are vetted and information given thoroughly verified. Most embassies (especially the UK and USA) share information on a lot of things and so if information you are giving is different from information in a previous application in another embassy, they could penalize you for it.
Lying on a visa application is a very bad idea. If they find out, they will not only deny you visa, they will make it almost impossible for you to visit the UK ever again and possibly any other countries they share that information with. And worse, if they find out after you have entered their country, you could face up to two years in prison or get deported. Note that lying and hiding information in visa application are regarded as same and leads to prosecution as well.