Or by following the instructions on the EOS website, but you can check here first to see what the current 'price' is http://eosscan.io/. But be aware that the price displayed is not the price you will pay, unless the countdown timer is almost at zero, even then there may be a last minute large investment. There are 2 million tokens distributed every 23 hours, the number of tokens you get, and therefore the price, is determined by how many ETH have been contributed in that 23 hour period. So it might have a price of 8 cents after one hour, but after 22 hours, 59 minutes and 59 seconds it's likely to be a lot higher, and if it's not, then the contributions are starting to tail off and the price on the exchanges will be a lot lower than the current $4.