London's one of the best cities in the world and you'll have a great time there. To make it even better here are 7 essential tips that'll make your visit cheaper and easier. Most visitors to London don't know about these tips and end up paying more for things than they have to.

1. 2 for 1 Offers

The Days Out Guide is one of those secret websites that's essential for any tourist wanting to visit London attractions. Instead of paying full price to see attractions such as Madame Tussaud's and the Tower of London, you can get in for half price with a 2 for 1 voucher.

All you have to do is register on the Days Out site and print off vouchers for the attractions you want to see. The only restriction is that you have to show a valid train ticket with your voucher at the attraction. However it's easy to get the train ticket. Just go to one of the overground stations such as Victoria, Charing Cross or Paddington and buy a Travelcard and make sure it has the symbol on it. Underground Travelcards do not have this symbol which is why you have to go to an overground station.

2. Hotel Reviews

Deciding which hotel you're going to stay at in London is easily one of the most important decisions you'll make. What most people do is head to Tripadvisor to help them make a decision. A few years ago you could do that and be pretty sure that the reviews were accurate. However over the last few months some people have been saying reviews are being written by PR firms for their client hotels. (Tripadvisor strongly denies this.)

Here's a tip to help you get around this problem. When you're looking at the reviews, first look at when the person became a member of Tripadvisor. If they've been a member from 2006 or earlier you can be pretty sure they're giving honest reviews.

For me, any reviews from 2007 onwards or from people who have only done one or two posts are as a good as worthless. Most of the hotels in London have been around for years, so look at those early reviews.

3. Exchange Rates

I feel so sorry for the tourists I see queuing up to be ripped off at foreign exchange booths in London or at the airport.

London is an expensive city, so you need to get the most for your dollar. To do this you really should order your pounds online. Travelex is one of the most reliable companies. You simply order online, and you can collect the currency at the airport.

Another alternative is to simply use your debit card in one of the ATM's at any bank in London. Check with your bank before you leave to see how much they charge, but it's bound to be cheaper than a foreign exchange booth.

4. Buying Booze

What do you do if you want to have a nice bottle of wine in your hotel room but don't want to pay the hotel prices? Most so-called London experts will say go to a supermarket and buy a bottle there. (This is absolute rubbish.)

The best (and I'd say, the only place) to buy booze in London is Gerry's on Old Compton Street in Soho. When I say you can buy almost any drink you've heard of, I'm not exaggerating. Prices are very good, and it's the only place you can pick up an authentic bottle of Prosecco for less than £10.

Also, when you decide to go out and have a drink, look out for happy hours. Many venues have them, but make sure you know what the restrictions are before ordering. The big sign in the window may say drinks are half price, but inside you find it's only on bottles of champagne! A way around this is to get the EPok London Pack, which includes a handy happy hour guide that lists bars and pubs with half priced drinks.

5. Free Walking Tour

London is huge, and a walking tour is one of the best ways to explore the city. If you're up to walking around for 3 hours, the Sandemans Free Walking Tour of London is a great option for you. The walk takes place every day, regardless of the weather, and you can just turn up and go.

6. Child-friendly Restaurants

Finding child-friendly restaurants in London isn't the easiest thing to do. It's not that restaurants in London don't welcome families; it's that many of them make no special arrangements for families.

One of the better chain restaurants for considering families is Giraffe. The cuisine is International, 2 course meals are about £15, and they have a special menu for kids and colour-in games to keep them happy. Their restaurants are nationwide, and the Southbank Centre and Victoria branches in London are good choices to try when you're here.

7. Taking a Taxi

London taxis have always been quite expensive, so Londoners only ever take them out of necessity. Tourists, on the other hand, look at them as part of the London experience. However, ask any tourist who took a cab along Oxford Street what they thought of the experience, and you'd have to cover your ears.

London has the slowest roads in Europe, and if you make the mistake of getting a taxi on Oxford Street, the Strand, or Haymarket, you'll be watching the world go by as you stay still. Treat yourself to a taxi ride because it's great, but avoid the above streets, and you're more likely to enjoy the experience.

If you follow these tips you'll save yourself a stack of cash and enjoy London a lot more.