The application process for tickets to the London 2012 Olympics opened at midnight last night, with organisers expecting the official website to be the world's third-largest online retail portal, after eBay and Amazon.

Locog, the Games' co-ordinating committee, can only estimate how many people will apply before the deadline on 26 April. But given that 2.5 million registered their interest in tickets in advance, the number of applications for individual events is likely to be in the tens of millions.

However, organisers have been emphasising that the process is "a marathon and not a sprint", so prospective spectators should not worry about missing out on those Greco-Roman wrestling tickets.

The process is not first-come-first-served; automated ballots will select tickets at random for oversubscribed events, and the window to apply runs until 26 April. There are 6.6 million tickets for the Olympic Games available to the British public in total. And with 645 sessions for 26 sports taking place at 34 venues across 19 days, there is plenty of choice available.

Nevertheless, as the biggest sporting event to ever take place in the UK, every event is expected to sell out. Even the less glamorous events such as archery, handball and synchronised swimming are on the wishlists of tens of thousands of people. The Korean martial art of taekwondo looks set to be a thumping big hit, and there could even be hearty cheers of "Britannia rules the waves" as Team GB competes in the water polo event at the Olympics for the first time in 56 years.

Where to apply for your tickets

Online at www.tickets.london2012.com or at branches of Lloyds TSB. Thomas Cook will be offering a range of "Games Breaks" in which tickets are included with accommodation, while Jet Set Sports have all-inclusive packages. Do not buy from anywhere else, as they are not legitimate vendors.

The most expensive tickets...

The best seats at the opening ceremony will cost £2,012.

...and the cheapest

There are 2.5 million tickets available at £20, covering every sport. Children aged under 16 can "pay their age", so a 12-year-old only costs £12. Some events are free: the men's and women's marathons, the cycling road race, walking races and triathlon cycling stage.

Best chance of seeing a British gold

Our highest hopes are with the cyclists, such as Chris Hoy and Victoria Pendleton. But as the velodrome holds only 6,000 people, their events will be massively oversubscribed. Instead, try getting off the beaten track and onto a bumpy one – Shanaze Reade is a real medal contender in the BMX racing, if you are after something a bit different that will not take up too much time, does not need in-depth knowledge of the rules and makes for great viewing.

The BMX arena surrounds an undulating course over which competitors bunny-hop (and crash), and it is right in the middle of the Olympic Park in the shadow of the velodrome. The action is squeezed into two-hour sessions over three days and Reade, who crashed in Beijing and ruined her medal hopes, should feature strongly.

If you want a cheap option with the prospect of British gold at the end of it, then the triathlon could provide one of the best spectacles of the Games. In the course of less than two hours, Alistair Brownlee will swim, cycle and run around Hyde Park and the Serpentine in pursuit of a medal.

Where to see Usain Bolt

Everyone expects the Jamaican sprinter to be in the 100m final on 5 August, but as that will be the most coveted ticket in town it would be wise to apply for the classification heats the day before as well. Don't forget that he also runs in the 200m and 4x100m relay events, so look out for those later in the month.

Not everything is in London

Events outside the Olympic village include football in Glasgow, Cardiff, Manchester, Newcastle and Coventry; sailing in Weymouth, Dorset; rowing in Buckinghamshire's Eton Dorney; mountain biking at Hadleigh Farm in Essex; and canoeing at the Lea Valley White Water Centre in Hertfordshire.

Maximise your chances...

If you really want to see one sport in particular, apply for several sessions across different days, especially earlier heats. And if you have your mind set on a specific final, mark yourself down for different price ranges. On the other hand, if you are less fussy about what sports you see, try some of the less hyped ones – such as handball or water polo.

...but don't get carried away

Although people applying for many different sessions are highly unlikely to get all the tickets they request, it might happen. Therefore work out what you can afford and set a strict budget before diving in – especially as you must have the funds available to buy whatever tickets you are allocated, and orders cannot be changed once they have been processed.

How to pay

Only Visa cards will be accepted on the internet. If you do not have a standard Visa debit or credit card, you can buy a pre-paid Visa card from a bank (you load cash onto the card to spend at a later date). Otherwise, you can apply for tickets using a cheque or postal order at branches of Lloyds TSB. Payments for successful applications will be taken between 10 May and 10 June, but you might not be notified of which tickets you have received until 24 June.

If it turns out you can't go...

A third of UK companies are expected to increase flexible working hours to allow staff to watch the Games. But if you cannot get time off or are unable to attend, a re-sale website will allow you to trade tickets at face value. You cannot sell tickets on eBay or other auction websites.

Advice for non-British applicants

If not a resident of the UK or one of the designated European countries, you will be required to apply for Olympic Games tickets via your local National Olympic Committee (NOC) from 15 March 2011 and Paralympic Games tickets from your National Paralympic Committee (NPC) from 9 September 2011.

Applications for corporate tickets

Only 1 per cent of the tickets will be for corporate buyers, but if you want some for your business you can apply online in the same way as for public tickets. Prestige Ticketing have exclusive access to official on-site hospitality packages.

Applications for the Paralympics

These open on 9 September, when 2 million tickets will be available.

With 500 days to go,

Olympic Park is on schedule

Sport, page 51