Lagos is not for the rookie traveller. You need to be street wise to avoid getting into trouble. The city is hot, dirty, but very full of life, totally African and very exciting to be in. It is not for everyonem, and not for more than a few days I think. The markets are the best attraction, where all the life concentrates. the cinemas also are fun, because the nigerian movies (the industry is called "Nollywood") are crazy and prolific (more than 2000 are made every year; $500 million dollar biz).
a traveller especially from a western country needs to check out the health hazards in nigeria of which there are many and get the vaccinations to reduce the risk of getting cholera, malaria, yellow fever, dengue fever, hepatitis B, HIV, hepatitis A, hepatitis C. You can book for travel vaccines at your GP centre but the yellow fever has to be done at a specialist centre which the GP can advise you where. You need to do these a couple of months before because some of them are a course of injections/tablets so dont leave it til the last minute. also your arm will be sore for a few days and you wont be able to carry your bag! honestly, though you need time to get them sorted about 6 weeks. also the Gp needs to get the vaccines in sometimes. Check the websit ato see how these diseases are spread as then you will be better prepared to reduce the risk of catching them. For example some are throgh mosquitoes ( some in the daylight other mosquitoes bite at night) dont wear aftershave or perfume as it atracts the mosquitoes. take some redhydration salts in case you get diarrohea because dehydration can kill you or at least make you disorientated/confused. you need travel insurance which includes evacuation as their hospitals are not really for westerners. It is much more dangerous for your health to be in these countries than a holiday in europe or usa. I have travelled there a lot and it is very stimulating/different enjoyable sceneray but you have to be very careful if you are travelling alone not to get taken advantge of by people who seem very friendly yet are after your money, your organs (kidney etc) and carry HIV, hepatitis B. Take good precautions and travel with other westerners. Hide your passport well and dont get into a relationship (passport hunters and god diggers and HIV carriers) Enjoy but be careful