To be quite honest I have forgotten the author of the following but I think it contains a lot of good advice.The scroll above says Xingyi all under heaven. It means that all things can be expressed or understood through Xingyi.
Practicing the method of Xingyi Boxing truly is a disease-preventing life-prolonging study in cultivating the Way. From my youth I have practiced medicine. Though this year I am almost seventy, my body’s movements are nimble, I seem still as strong as in the prime of my life, and I have not needed medicines to maintain my health. The method of this boxing art is the principle of nourishing energy to cultivate oneself. It effects are demonstrably true and it genuinely seems to serve as a panacea. However, practicing boxing is easier than realizing the Way, and realizing the Way is much easier than cultivating the Way. Therefore in practicing boxing arts, the first thing of importance is to obtain the authentic teachings, which convey the standards of practice within the boxing, for once you know you have the real thing, you will train according to the proper learning sequence. The second thing of importance is to truly cherish it. The third is to be of a persevering mind, making it the task of your whole life to master it. Without these three things, then even if you are practicing, it will be as was said by an ancient man [quoting from the Da Xue]: “If your mind is not on what you are doing, you will look and not see, listen and not hear, eat and not taste.” This is to spend your whole life on it and be unable to obtain it. Real sincerity possesses the principle of training with a mentality of perseverance. Although you may obtain a little, you cannot be complacent. Therefore in practicing the postures and principles, you also should frequently seek out instruction, looking to all of those from the older generation of teachers. Some ancient man said: “Since no one is perfect, who is it that can make no mistakes?” If you are proud, then usually whatever you get out of the principles will often go ignored soon after. With the principles neglected, your boxing art will give rise to countless errors. (And errors in boxing arts are not such as a person can take medicine to cure.) If errors are obvious, they can still be easily fixed, and a teacher of either greater or lesser skill, with either a deep or superficial understanding of the theory, can make corrections. But if errors are hidden and complex, then even a teacher whose theory is very deep and is backed by a wealth of experience will be unable to cure you of such maladies. Complex errors are when the source of a problem with the head does not lie in the head, or of a problem with the foot not in the foot, or of a problem on the inside of the body not there, or a problem on the outside of the body not there. Hidden errors – those that seem invisible yet visible, or to be there yet not to be there – are common enough in a person’s training and do not get discerned as errors. If you are aware of them yourself, they will be no trouble. By thinking about the principles in what you practice, you will become skillful. But without knowing your own errors, how can you attain a deeper level? If you do not obtain a thorough and profound understanding of the art’s theory and method, you will not be able to fix these errors, and if not, then though training day and night, you will be for your whole life unable to get it right. These errors are considered to be of a crude and ordinary kind of strength, in the same league as a commoner’s use of exclusively straight lines when writing calligraphy, and is no better than having a theory that from beginning to end cannot help you progress. A practitioner of boxing arts who is very skillful with his whole body and very brave in competing with others – it is easy to find seven or eight such people among ten. But one who can instruct others, whose skill is so good, whose movements are so harmonious, whose analysis of the theory is so clear and detailed, that he can get others to easily understand and is a model for the next generation of students – it is difficult to find one or two such people among ten. How to practice: spirit and energy are coursing through, and the form is harmonious, hardening and softening, twisting and turning, lengthening and shortening in the proper degree. It is the same principle as in Zeng Guofan’s discussion of calligraphy, in which he says “[Everything comes from] the two trigrams of Qian and Kun”. [Kun (“accepting”) represents the formalized external postures, while Qian (“striving”) represents the personality of the spirit within.]