Can any 1 let me know how to move app to sd on my s3..cos I been trying a lot of staff...but still can't

It can't be done on the S3 without root. Google is trying to get manufactures to move away from using microSD cards altogether, but for those who choose to include them, they can now only be used for personal files (music, videos, pictures, documents, etc.).

We have an ongoing thread about the topic here: Galaxy S3 moving Apps to external SD card Issue. Since it's more beneficial to the entire community to keep all conversation on the topic in one place instead of spread out across several threads, I'm going to close this thread. Read through the posts there (which also talk about an app that, with root access, will let you install application data on the external SD card), and feel free to post any further questions or thoughts that you might have.