Note: I took some of these images from coinprism's blog so credit where credit is due.
The first step is to create a wallet that is color aware. You can use coinprism.com or if you have an android device, install their app from play which you can find here
If you choose to use coinprism you will need to setup an account. coinprism signup page
The next step is to fund the account that will own the colored coins.
Once your account has been funded you can then send the appropiate amount of funds to the respective asset address of the coin you wish to purchase. You can find the asset address for the asset or coin you wish to purchase on their coinprism profile page.
The asset address we will use for this demonstration is the one I am running.
When the next batch is processed for the crowdsale you will find your coins in your wallet.
If you chose to use another wallet that is color aware the same steps apply only from within that app or wallet.