The 10 things you must do to stop throwing money away: Sarah Coles

Making the minimum payment on your credit card. Minimum payments are a menace, designed to drag you into borrowing for far longer than you need to, spending a small fortune on interest in the process. If you have expensive credit card debts, the best approach is to free up as much cash as you can from your budget and pay them down as fast as possible.

Forgetting to make at least the minimum payment on your credit card. You’ll face a fee if you miss a payment, but this may be just the start of it. In some cases, the credit card company will remove perks like 0% on balance transfers, so you could end up with hefty interest payments. Pus, if you miss the payment entirely instead of just paying slightly late, you’ll also damage your credit record. It’s best to set up a direct debit to make sure you never forget.

Not acting fast when something is wrong. When you order online, you have 14 days to return an item for whatever reason you choose. After that, you can return faulty items, but it will be up to the retailer whether to accept returns for any other reason. Similarly, if something arrives broken, or breaks soon after you get it, it’s best to return it within 30 days - during which time you’ll usually get a full refund. After that, they may insist on a partial refund, exchange or repair. If you wait more than six months, you’ll need to prove the item was faulty when it was sold to you.

Being upsold. The classic here is TV and broadband packages, when you call to cancel and come off the phone having increased the size of the package for a bigger monthly fee. If you think you might be vulnerable to this and you’re calling to cut your bill or cancel, get someone to sit with you while you do it, to keep you on the straight and narrow.

Making the wrong move when your phone contract runs out. The worst possible thing you can do is nothing, because at this point, you’ll have completely paid for your phone, but you’ll carry on paying instalments on it as part of your monthly bill. The second mistake is to upgrade if you don’t really need to. Think carefully whether you genuinely need any new features on your phone. If you don’t, you can switch to a SIM-only deal, where you just pay for minutes and data for less than £10 a month.

Tying yourself into restrictions you can’t meet. This applies to all sorts of spending. Advance train fares with no extra time built in for delays may be cheap, but they’re non-refundable, and the replacement journey can be painfully expensive. Similarly, a savings account offering a higher rate in return for limiting withdrawals is going to get much less rewarding if you underestimate how many times you’ll need to dip in.

Not checking insurance exclusions. There are some reasonably widely known ones, like the fact that if you have a few drinks on holiday and then have an injury, your insurance may not cover you. However, insurers can get wildly creative with exclusions, so check them all. I have just found myself unable to claim on an insurance policy because the phone that was crushed in an unfortunate gym-related accident was more than three years old. It was actually only three days past this deadline, which made it even more annoying.

Leaving things to the last minute. This applies almost across the board. Insurance, for example, is more expensive if you buy a policy to start immediately, because insurers think that people who apply three weeks in advance pose less of a risk. Likewise, train tickets cost more the closer you get to the time of departure. Then there’s the eye-watering cost of leaving exchanging your holiday currency until you get to the airport. The only real exceptions to the rule are where you get close to the deadline and businesses are trying to shift unsold items – which is when you can get bargain flights or holidays.

Buying something for a lifestyle change you never actually implement. It’s a particular risk at this time of year, when we sign up for a year at the gym and go twice, or buy exercise equipment that ends up gathering dust. However, it can happen at any time, and involve any kind of change. It’s why our homes are full of unridden bikes, unused breadmakers and vegetables from box subscriptions going mouldy in the fridge. The best approach is to try the lifestyle out first, possibly by borrowing the equipment or making do with what you have, and only spending money once it has stuck.

It's worth being aware of all of these things, and taking steps to avoid them. However, it’s clearly not entirely foolproof, otherwise I wouldn’t have fallen foul of half of them – plus of course that horrible cancelation fee. On an entirely unrelated note, would anyone like to buy an ugly dress from a shop that doesn’t take returns if you change your mind?

Sweat your savings

Saving is the ‘going to the gym’ of the financial world – there’s a vast gulf between what we know we should be doing, and what we get around to. We know we should be switching for the best possible deal, but plenty of savers leave cash languishing in high street easy access savings accounts. We also know we should be fixing portions of our savings for a better return where we can, but we often leave it in easy access just-in-case.

But sweating our cash more effectively could leave us thousands of pounds better off, and is even more important in an environment of falling rates. Moving £30,000 from the average branch-based easy access account with a high street giant to the best on the market could leave you £4,618 better off over the next five years. Fixing it for five years at the best possible rate could make you £5,830 more in interest.

So even if you go nowhere near the gym this January, it’s worth making the effort to sweat your savings.