It's never been easier to have a Grand time

At this busy time of the year for sports, it can really pay to know your betting options, writes James Daley

(Independent Graphics)

The biggest betting event of the British sporting calendar gets under way at 4.15pm today – a horse race that attracts some 600 million television viewers worldwide, and hundreds of millions of pounds in bets from punters. For many, the Grand National is the only event all year that'll tempt them to have a flutter, with most disregarding the horses' form in favour of catchy names and lively racing colours, when it comes to making their selection.

Although historically, placing a bet has tended to mean taking a trip down to the local bookie (followed by a 10-minute headscratch trying to work out how to use a betting slip), the growth of the internet over the last few years has seen dozens of new bookmakers springing up online, each offering ever more generous incentives for punters who are willing to open an account.

If you can bear to live without the thrill of collecting your winnings over the counter, opening up an online account can be a great way to ensure that your one bet of the year costs you absolutely nothing. Furthermore, you're also likely to find better odds than you might get down the local shop.

For the regular punter, who continues to use their account once the big race is over, there are even bigger incentives on offer – as much as £250 in free bets on some sites. And through exchanges such as Betfair, you can even take a turn as bookmaker yourself, taking on other people's bets that you think are going to lose (known as "laying" a bet).

Craig Hughes of freebets.co.uk, a site that lists most of the account-opening incentives, says that spring tends to be the best time of year for freebies, with the Cheltenham Gold Cup and the Grand National – Britain's two biggest steeplechases – running within a month of each other. However, he warns that it's important to read the small print before you sign up, as there are often a number of hoops you have to jump through to qualify for the bonuses.

"Often to get the free bet, you have to bet quite a substantial amount," he says. "And although the terms and conditions will be there somewhere, it's not always immediately clear in the adverts."

Most incentives require you to make a minimum first bet (or series of bets) worth £25, for which you'll receive a free £25 bet in return. However, others will match you from much lower amounts. For example, Betfred will match you from as little as £5, or up to as much as £50 – i.e. if you bet £50, you'll get a free £50 bet (and another £50 bet if you make five more bets of £10 or more).

Totesport will also match you from as little as £5 – all the way up to £25. So, if you only want to stake £5, you can still get another free £5 bet.

With 40 horses to choose from, picking a winner on Grand National day is no easy task, so it's also well worth watching out for the other special offers online that can help increase your chances of collecting a payout. For example, Victor Chandler promises to offer a free bet (worth the same as your original stake) to all punters whose horse falls or unseats their rider during the race. Given that the number of fallers usually runs into double figures, this could prove a worthwhile insurance.

Alternatively, if you're super-confident that you've managed to pick the winning horse, you might want to place your bet with Paddy Power, which promises to add 10 per cent to any winning Grand National bets. Furthermore, if you're making an each-way bet – which in a handicapped race, such as the Grand National, will usually pay out (at a quarter of the odds) if your horse finishes in the top four – you might also plump for Paddy Power, which pays out on the first five horses. If your priority is simply searching for the best odds, however, you're probably best served by Betfair – which will also offer you a free £25 bet, once you've staked more than £25 on its exchange.

Betfair is not a bookie – it's an exchange where "backers" and "layers" are matched off against each other. So if you wanted to back the favourite, Cloudy Lane, four days ago, you would have found hundreds of people willing to take a bet from you at odds of around 7-1. Before your bets are matched up, Betfair ensures that there's enough money in their account to pay you if you win.

Alternatively, you might decide that you want to "lay" a bet for Cloudy Lane. Tony Calvin of Betfair explains that this effectively amounts to placing a bet on every other horse in the race. Hence, if you laid a £10 bet at 7-1, you would have to pay out £70 if that horse won the race. If it didn't, you would receive the punter's £10.

Beware, however, that your stake is not returned if you back a winning horse on Betfair. So to compare Betfair odds against most other bookies, you need to subtract one from the odds (i.e. odds of 7-1 on Betfair are equivalent to 6-1 elsewhere). Finally, it's also worth noting that Betfair will take a commission of up to 5 per cent out of your winnings (although this decreases the more you bet).

For more information on the different kinds of bets you can make on Grand National day, visit www.grand-national-guide.co.uk