This braid uses 8 strands - 4 each of two colors. This example was made with standard embroidery floss. Cut your strands 30% longer than your intended finished braid length if you're using embroidery floss, other materials may require different amounts.
Start your braid with 4 strands of one color on the left and 4 strands of the other color on the right. Move the strand that is farthest right to the inside left; then move the strand that is farthest left to the inside right. Repeat this until your braid is the desired length.