On the other hand what is slang and what is dialect? Watch 'The Darling buds of May' for Kentish accents. You will find such programmes fun even if you don’t understand every word. They could lead to bad habits though. You may end up referring to your wife as "'er indoors" or pronouncing ‘God ‘ as ‘Gawd’ and talking about the ‘perfick’ weather. What it will do though, is enrich your knowledge of English in a positive way and this is the aim after all.
Here are some examples of slang:-
Londoners might refer to ‘Apples and pears ‘ which rhymes with stairs. They talk too about ‘my old china’ which I short for ‘china plate’ which rhymes with ‘mate’. Funnily enough in Yiddish ‘Clinah’ or ‘Cliner’ is a sweetheart.
Some words are associated with particular versions of English – ‘Dinkum’ is Australian for ‘Good’ or ‘True’ as in ‘Fair dickum, mate’. This is fine in Australia , but sounds a little out of place elsewhere.
Do remember though, before you try to use any slang, that lots of slang words are considered to be extremely rude. Make sure you really understand what a word or phrase means before you introduce it into conversation, unless you want to be rude of course.
Other words may be associated with crime, especially illegal drugs, so are best avoided if you want to make the right impression.
I hope I’m not putting you off using these colourful metaphors and phrases. They add variety and liveliness to any speech and if they were good enough for Shakespeare, they must be good enough for you. Loads of things he said for the first time are now part of everyday English - ‘elbow room ‘ meaning room to move; ‘to be eaten out of house and home’ - used when a greedy guest uses up all your resources; ‘the apple of one’s eye’ refers to something very dear to you. There are lots more
Some slang you can work out the meaning of, but there is lots more when it is virtually impossible. I’ve just been looking at a novel set in the 1960’s, and even though I was round then, it might as well be in Dutch.