Tax help

Hi guys
was wondering if anyone can help me with tax return for my shares. i bought and sold a few times in LNG. Now i don;t know how to calculate which shares i have sold from as there are quite and a few buys and sells within the one year time frame. also i have made good profit in 13/14 and huge losses in 14/15. i want to use a method that would minimise my capital gains for 13/14 financial year.

Thanks

p.s i know it is very late for 13/14 tax return