1-Start with a basic circle.

2-Add curved, vertical lines as shown. The center line is straight.

3-Add curved, horizontal lines as shown. The center line is straight.

4-Add continent shapes.

1-Start with a basic circle.
2-Add curved, vertical lines as shown. The center line is straight.
3-Add curved, horizontal lines as shown. The center line is straight.
4-Add continent shapes.