Tai Chi principles #1

Straightening the Head - Stand straight and hold the head and neck naturally erect, with the mind concentrated on the top. Do not strain or be tense; otherwise, the blood and vital energy cannot circulate smoothly.

From the book "Yang Style Taijiquan" by Yang Zhen Duo

When starting your journey this is the first principle you should focus on. A lot of new students always ask about breathing such as when and where should I breathe? I always tell them to breathe naturally and focus on straightening the head and to try and relax.