How do you Swim in the Olympics?
To swim in the olympics, you have to be selected for your country's olympic team, which will typically be selected in the year leading up to the competition. Selection usually occurs at a national qualifying event, which you must achieve a qualifying standard to enter.
In some countries the qualifying standard for the event must be met at a certain level of competition. Usually up to two atheletes will be selected for each olympic swimming event, but some teams will choose not to enter an event if they do not feel that they can compete seriously with the representatives from other countries.