To participate in an Initial Coin Offering (ICO), you will typically need to purchase the cryptocurrency token being issued by the company. You can purchase these tokens from a variety of exchanges, such as Coinbase, Kraken, and Binance. Once you have the tokens, you can then send these to the company’s ICO address, usually noted on their website. The tokens will be sent back to you, along with any bonuses or discounts the company may offer.