Over to you
When noise levels rise, put a Q for "Quiet, please" on the board. If it's still too noisy, put up another Q. If you have to write a third, the whole class stops, you explain that it has become too noisy for people to work and you have a sanction of, say, five minutes' silence. This non-verbal communication is sure to get the class's attention.
Save your voice
When taking the register, say "good morning" to the first child, who then says it to the next child in the register, and so on. The last child should greet you, "good morning MrMs". Try these greetings in different languages as well. "Namaste (HindiGujerati); meher baan (Turkish); bonjour (French); guten tag (German); kalimera (Greek); shalom (Hebrew); salaam alekem (Arabic).
If any pupils are being noisy, don't waste time and give them attention by telling them off repeatedly during class. Write their names on the board, and when they talk or disrupt the class put a tick beside the names. Any child with two ticks must see you during break to explain their bad behaviour.
Make word ladders to introduce new vocabulary in numeracy. Use strips of ribbon or paper as the sides of the ladder, then print each word on both sides of an A4 sheet and cut them out. Staple the words (in order of introduction) as "rungs" between the ribbons, with gaps of about 5cm between each word. The ladder can hang from the ceiling, so wherever children are sitting they will be able to see and use the words.