A noticeable difference between Osaka-ben and standard Japanese is the plain-form copula. While the standard plain form copula is 「だ」 , Osaka-ben uses its own copula, 「や」 .
It's really that simple. However, you should note that 「や」 can be used every time that 「だ」 is used in standard Japanese.
(For now feel free to use 「やった」 , however please keep in mind that later you will be taught another plain-past copula used with な adjectives and plain-past-negative verbs- this also applies to the below “tara” conditional, as it is essentially just a modification of plain-past form).
There is one exception to this rule: the 「のだ 」/ 「んだ」 structure.
In Osaka-ben, this structure becomes 「ねん」 .
Standard Japanese: ちょっと寒いんだけど。。。
Osaka ben uses standard Japanese sentence ending particles, such as 「ね」 and 「よ」 . However, it also has its own sentence ending particles. Most can be considered counterparts to the standard versions, however there are also some particles in Osaka-ben that are completely removed from standard Japanese. 「ねん」 , introduced above, is one such example of one of these “custom” particles. Although is has, for all intents and purposes, the same meaning as 「のだ」 , 「のだ」 is a grammatical structure whereas 「ねん」 is a sentence-ending particle.