1. We first prepare materials: tape, a conical paper tube, pencils, plastic straws, and scissors.

2. Then we first flatten one end of the straw with our hands and pinch it several times, as shown in the picture below.

3. Then use scissors to cut the flattened straw into a pointed end and divide it into two halves, as shown in the picture below.

4. Then we use a pencil to draw a line around the top of the cone, as shown in the picture below.

5. Then continue the previous step and use scissors to cut along the drawn line, as shown in the picture.

6. Separate the cut tips of the straws on both sides of the cone, and then tape them together, so that a handmade trumpet is ready.