1. First Purple Coin

Continue running forward. Then underneath the first Surprise Question Block that is between the L-shaped row of bricks, jump under the block to get the first Purple Coin.
2. Second Purple Coin

Once you see a pair of bridges with an opening in the middle, jump in the middle to take the lower bridge platform in order to get the second Purple Coin, which will be in between two Gold Coins and a row Dash buttons.
3. Third Purple Coin

As you move forward, you will come across the Pause button with a curve of Gold Coins floating right above the said pause button. Before jumping on the flying Koopa, make sure that it has gone as low as possible already. When you’ve jumped on the flying Koopa, the shell from that flying Koopa will glide through the nearby box of bricks where the third Purple Coin is located.
4. Fourth Purple Coin

Right after getting the third Purple Coin, you will see a Koopa Troopa walking across a row of bricks. Walk beneath this Koopa Troopa and jump underneath it to send its shell flying toward the side. Once you see the shell lying around, run towards it to propel it forward.

Follow the Koopa Troopa shell until it falls through a ledge and breaks a column of bricks and hits the Surprise Question Block right beside a bridge.
5. Fifth Purple Coin

Continue running forward and then jump on the springboard that’s right underneath the row of bricks above it in order to get the fifth Purple Coin.