Start by talking with your current lender about what they may be able to offer you. If you wish to look at a significant overhaul in features and benefits of a loan product you may be better placed to receive advisory from a mortgage broker for unbiased product advice.
The idea is to establish what costs are involved if you do go ahead.

Decide what’s right for you. The offers you receive will vary from borrower to borrower, depending on factors such as your income, living expenses, and whether your finances are likely to change in the short- to medium-term.

Consider the features you need, such as a an offset account (or even multiple offset accounts), redraw facility or lower fees. Whilst there are plenty of loan options available, it’s vital you take the time to review them thoroughly, bearing in mind your unique circumstances and the types of features you need. 

There’s no point refinancing if you're only going to end up in the same situation or even worse off.

It’s also worth considering whether an online lender can better meet your needs. Such lenders tend to offer highly competitive rates without the overheads weighing down those lenders with physical branches, making them potentially better suited to devising the perfect home loan for you. Your mortgage broker can run comparisions on hundreds of different lenders and products making it easier to find the best loan to suit your needs and ensuring the right fit.

After you've decided on your ideal loan product, it’s time to submit your refinance application.

Just as when you first applied for a home loan, you’ll need to provide various documents that prove you can make good on your loan if you wish to refinance your mortgage, particularly if you plan to switch lenders.

Your new lender will let you know what information they require. Your mortgage broker will help you with this step.

After you sign this agreement, the lender will register the mortgage on your property. It then acts as a security on your new loan.