Good Afternoon if I am understanding correctly you would like to know how one increases their ability to communicate effectively in another language utilizing the methods you noted below the question. In doing so you must define each of those and practically apply them to your communication efficacy.
1.Mechanics of Sound:When learning a new language you must consider the physical components, the "how"of that language which includes mouth movements, tongue placements as well as intonation (rise fall of words) what part of words have more stress or emphasis on the word can totally change the word perception. This includes the ability to hear how native speakers use sentence structure, syllable stress influence, to distinguish correct pronunciations.
Age: Biological age can influence the ability of to learn language as far as timing acquisition of that language. Children have a higher percentage of learning languages especially with mimicking the native pronunciation more quickly than adults due to what's called neuroplasticity. The adult brain however has a higher metacognitive structure so they are able to approach learning a new language through planning, understanding rules and grammar, and more explicit intentional methods.
Motivation: You must take into account both extrinsic and intrinsic motivation: both are reward based regarding what you value.
Extrinsic: Lets say your job is requiring you to learn a new language to communicate with clients and in return you receive a raise or you are demoted. You also happen to be an avid comic-con fan and could use the increase in cash, but would also like to keep your current pay scale. So you do so which gives you a paycheck so this motivates you to keep your paycheck because you don't want to be broke so you will learn the language.
Intrinsic: Lets say you have someone important in your life who speaks a different language or just you enjoy the culture of lets say Italy. The motivation for you could be love of a person, or the respect of the culture you wish to show that respect for to immerse yourself in the culture , understanding it more through mastery of language, getting around the country, ordering food, exploration. etc. Both of these motivations will increase practice frequency, willingness to speak, engagement.
Opportunity: Where, when and how often. People learning a new language benefit immensely from active opportunity such as real time practice, immersion into the culture learning staying in the country, tech apps real time communication with others.
Ability: Could refer to cognitive ability being able to process what you hear, memory skills, word recognition understanding rules of grammar. Ability is not what is know as "fixed" you can improve through practice.
Realistic expectations: You will not learn all the nuances of a language in one day. There is more to learning a language than just learning the words or grammar, sentence structure, fluency can take years. However, that should not deter you. Setting achievable goals will help will encourage growth and momentum. Reward yourself. Have brief conversations so you can see your hard work in real time, putting a rewards list if you practice so many minutes, etc.
Hope this helps.
