Any documentation on how to finetune/train on custom pair dataset?

[KenWuqianghao]

I read through all related issues, and there doesn't seem to be a comprehensive doc on fine-tuning the custom pair dataset.

How would I go about doing this?

The information given at #75 is unfortunately not enough for me to figure out how to process the data and set up config properly.

Please provide a bit more guidance and it is greatly appreciated. @IceClear @chenxwh