Use register (frozen, formal, colloquial, informal and intimate), technical language and idiom as appropriate to the subject matter, context and their relationship with other

Get to grips with the five levels of language registers: frozen, formal, colloquial, informal and intimate. These are based on the level of formality and appropriateness in a given situation.
Recognise that frozen language is a fixed form of language that does not change. It usually pertains to ceremonial or ritualistic language.
Understand that formal language is used in professional settings and is characterised by complete sentences and specific words.
Be aware of colloquial language which includes local or regional dialects. It’s less formal and often used among familiar groups.
Understand informal language as the relaxed language commonly used among friends and family.
Recognise intimate language as the kind of language used amongst very close relationships such as family members or loved ones.

Be comfortable with technical language related to specific fields or professions. This sort of language can include jargon or specialised terminology.
Identify idiomatic expressions which are figures of speech where the phrase’s common meaning does not add up to the literal meaning of the words.

Develop the ability to adapt your usage of language register, technical language, and idioms according to subject matter and context. It’s important to know when to use formal versus informal language, or when certain idioms or technical terms are appropriate.
Build awareness of one’s relationship with conversational partners. Different relationships warrant different levels of language register - for example, a more formal register would be used with a teacher or authority figure, and an informal or intimate register would be used with close friends and family.

Understand the right setting and conditions to use varying levels of language register, especially for more formal and technical language.
Know when it’s acceptable to use colloquial language, typically in casual or informal conversations with familiar people.
Practice the use of idioms as they can greatly enrich your communication and help convey ideas in a more colourful way.

Familiarise yourself with shifts in registers according to changes in the situation, audience or subject matter. This indicates a good command of British Sign Language.
Cultivate the ability to suitably adjust your language to the level of formality or informality required in a given conversation.
Understand when to incorporate idiomatic expressions or technical language, ensuring they are fitting with the context and the receiver’s understanding.