There was a time when Ripple offered a trading platform to sell directly to customers. Due to their desires to become a more decentralized currency, they did away with it.
I will tell you step by step, how to get XRP with a credit/debit card/Paypal, and fast.
First you need to open up a Coinbase account. This will allow you to buy one of three coins (BTC/ETH/LTC).
When making the coinbase account, be sure to add 2FA (2 Factor authentication). I use the Authy app.
You will also need to put a debit/credit card OR Paypal payment method. This is the only way to instantly buy coins on Coinbase.
After that, you need to decide which destination to put your XRP on. Current supporters are Gatehub, Bitfinex, Bittrex, and Poloniex. In that order, they are from most secure to least secure in my opinion. Do your own research on each! Don't forget to put the 2FA on those sites with the authy app.
Now you have a means of buying coins with USD instantly on Coinbase. You also have a ripple wallet destination to send them to.
The next part is getting an account on Changelly set up,which is fast. This is how you will simultaneously convert/transfer Coinbase coins to the wallet you chose.
Now, instant buy any coin on Coinbase, with the payment method you chose. Then go to Accounts. Click on the Coin you decided to buy (BTC/ETH/LTC). Find the wallet address.
In another tab, open up your ripple wallet. (Gatehub/Bitfinex/Bittrex/Poloniex) . Hitting deposit will bring you to your XRP wallet on any of these sites.
In any of these accounts, look for the XRP wallet address.
Once you have that, open up Changelly. Your currency bought on coinbase will be converted to XRP. So, pick the one that you chose to buy.
It will ask for the amount. Send a little less than you bought on Coinbase, in order to be exact and avoid any transaction problems.
Next it will show you how much XRP you will get for that coin. Proceed to give Changelly your XRP address. (You can copy and paste it, and it will likely start with an "r").
Hit next. Changelly will be waiting for that amount you bought on Coinbase. It will give you a wallet to send the Coinbase funds to.
On Coinbase, go to send. Send the same amount you entered in on Changelly, to their wallet. They are expecting that amount.
That is basically all there is to it.
You are going from Coinbase to Changelly. They will convert your coin into XRP and send it to your XRP wallet.
If you have any questions, ask in the comments. I will do my best to further elaborate this post and update it if any changes occur in the process.
I wish you all the best of luck in buying a very stable cryptocurrency!