Which type of braiding is least likely to cause tension on the scalp when installing extensions?

Flat twist braiding is least likely to cause tension on the scalp when installing extensions due to its technique and structure. In flat twists, the hair is twisted close to the scalp in a manner that distributes the weight more evenly across the scalp. This method allows for a more natural movement of the hair and minimizes pulling, reducing the risk of tension-related issues such as traction alopecia.

The other techniques, such as cornrow braiding and box braiding, often involve tighter sections and a more secure grip at the roots, which can lead to increased tension on the scalp. Fishtail braiding can also be tighter depending on how it is executed, potentially causing discomfort. Therefore, flat twist braiding stands out as the most gentle option for the scalp, making it a preferable choice when considering the health and comfort of the client.