Remove the first letter of the word then add an "a" at the end.
English: Old gent black tophat with a gold watch
You take the first letter of a word and put it in the end, then add 'ay' on the end. It's hard at first but the more you do it the easier it becomes to understand.
Backslang -'Udeday, heckcay utoay hattay irlgay, he'dsay etgay tiay osay ardhay'
English -'Hello there, how are you?'
Backslang -'Ellohay heretay, owhay reaay ouyay?'
Gillgi gillagow gillagar gillagou, would translate to Hi, how are you?
Millamat millamar millamou millamup millamo, would translate to what are you up to.
There are quite a few variants on it but all basically follow the same rules. "something" in between the syllabols of each word. Sound confusing? It is at first but at least i'm not tryin to explain double back slang
The type we would use was much more simple than some out there and would basically involve us putting "aag" inbetween syllabols (and also wt the beginning if the word begins with a vowel)
W"aag"ould y"aag"ou l"aag"ike "aag"an "aag"expl"aag"in"aag"ati"aag"on "aag"of b"aag"ack sl"aa"gang
Would drag out your sentences so not perfect but daagid thaage jaagob ;)