What is the recommended base to use along the front hairline to prevent splits or breaks in the finished style?

Using a triangular base along the front hairline is recommended because this shape allows for better distribution of hair weight and provides a more natural lay of the hair. The triangular base follows the natural contours of the head, which helps to avoid creating tension or stress that can lead to splits or breaks. Additionally, this base shape can enhance volume and can be styled more effectively, as it accommodates the natural flow of hair around the forehead.

In contrast, the other base shapes may not provide the same benefits. For example, a square base may create harsh lines that do not blend well and may put uneven pressure on the hair at the front, leading to potential breakage. An oblong base could also disrupt the smoothness needed at the hairline and create awkward angles. A rectangular base, while functional for certain styles, might not contour the hairline as effectively as the triangular base, making it less ideal for preventing splits and maintaining a seamless style.