Choose a wallet program, several are well suited for receiving DASH safely. It is recommended to then transfer the DASH from this working "soft wallet" to a "cold storage wallet" if you intend on saving the DASH or to an exchange.
Here are a few different DASH wallets to try:
DASH Electrum Wallet
Dash.org Wallet List
One nice thing about DASH is that you don't need to have a computer on hand when you recieve it. Many wallet programs have QR codes they will generate for your "public address" or "DASH Recieving Address." Always remember to write down your wallet seed! If you lose your seed and are unable to access your wallet no customer support exists to retrieve the funds, it is the same as losing cash at that point. However, the benefit to this is the assurance that your funds are controlled by you and only you, for you are the only one that should ever know your personal seed.
With your wallet public address on hand at the time you need to conduct your transaction, just have your client send the funds to your wallet address.