Because you have already bought shares your tax minimisation...

Because you have already bought shares your tax minimisation options are more limited

There are only 3 options that are really avaliable that wont come back and bite you at some time in the future.

1.

Sell shares you are sitting on a loss on in the same year. Far better to use the loss to reduce this years gain than to realise the loss in future years and potentially not be able to use it for a few years.

2.

Look at some form of negative gearing and prepay interest in the current year either on property or a share portfoolio that the interst will be deductible against

3.

Place money into super either either in your own name or through salary sacrifice if you are an employee.

But end of the day the 50% discount on capital gains after 12 months which means you will not pay more than 23.25% tax on the gain and that is only after you exceed $150K is about as good a deal as you are going to get and still keep it legal.

Assuming of course the gain you are postinng about is in this year. If it was realised prior to 30 June then there is nothing at all you can do.