Editor's note: this a sponsored post from PolicyBee - our insurance partner and sponsor of the Copywriting Conference.

When the words flow and hitting deadlines is as easy as picking off targets in a fairground shooting gallery, life is sweet. Work rolls in, clients are happy and invoices get paid – no questions asked.

But what if things aren’t quite so rosy? What if there’s trouble at t’ (content) mill?

The thing is, copywriters, like anyone, can make mistakes –­ whether it’s a literal error or something bigger, like an error of judgement.

And mistakes can be costly – especially if you work alone and there’s no one else to help carry the can. At their worst, mistakes can mean losing your clients, losing your reputation and ultimately, losing your business.

So you need to know your enemy. Because forewarned is forearmed, as they say.

To help you stay ahead of the game, here’s a heads-up for four typical ways copywriters can land themselves in trouble – plus advice on how to give hot water the cold shoulder.

Agree a contract

To kick off a project and before work starts, you need a contract that clearly sets out realistic expectations for both sides – signed if possible. If you’re unlucky, not having one can be the precursor to (whisper it) an accusation of negligence.

Sounds dramatic, maybe. But say a client’s domain authority remains determinedly static even after you’ve revamped their website with new SEO-savvy copy. What if they’d anticipated going straight to Google page 1?

Or you’ve crafted what you’re convinced is a winning direct mail campaign brimming with persuasive prose. Yet your words fall flat and the spike in sales your client was expecting fails to materialise.

If a client’s unhappy with the way things turn out and thinks it’s because your work wasn’t up to snuff, they may come after you for compensation. That’s why it’s important to get everything down in black and white first.

It’s not going to guarantee you won’t be sued, but it’s a good place to start.

Get sign-off certainty

Mixtakes are all too easy to make, eh? A simple slip of the keys here, or a paragraph dashed out under pressure of deadline there, can mean errors in your work.

Plus, there’s the perennial problem of writing on subjects you’re not really too sure about.

What if you’ve taken on a job writing complicated legal, financial or medical copy, and your knowledge base falls some way short of ‘expert’?

Getting things wrong at that level can have severe consequences.

The trick is to get everything signed off by your client. Never hit the WordPress ‘publish’ button, send a Tweet, or email copy over to a printer without first putting it in front of your client and getting signed approval.

That’s your proof they’ve seen your work.

And that’s important, because it’s an accepted legal precedent that sign-off means they take responsibility for it. It doesn’t always prevent claims, but it does help prove when/if mistakes were made by you.

In reality, you’ll probably work together to fix whatever’s wrong. But proof of a simple initial ‘thumbs up’ can act as an invaluable shield if things turn nasty.

Don’t be a copycat

When deadlines are tight, you’ve got other jobs backed up and there just aren’t enough hours in the day to keep all your clients happy, corners can get cut.

Maybe you cut-and-paste a section from your notes ­– forgetting that you lifted it directly from another website. Or you include a few paragraphs from an article you’d written previously – only you’ve already signed away copyright to the client.

Copyright is something to be both aware and wary of. It’s important because if you infringe someone else’s copyright by reproducing work they own, they’re within their rights to demand compensation. That goes for ideas, too.

‘Borrowing’ someone else’s words might seem like a risk worth taking when you’re up against it. Especially if you do a few mental calculations and reckon the chances of anyone actually noticing are slim.

But the fact is, content banks crawl the web looking for unpaid-for text. And although some are keener on legal action than others, all want payment.

It’s the same with pics; so if you’re supplementing your words with images, make sure you’ve already sought or bought permission for use. Always check the precise terms of an image licence too – it might include limits on where and for how long you can use it.

Remember that even if you’ve got sign-off from a client, the copyright buck stops with you.

Treat Twitter cautiously

Copywriting for social media is an art in itself. But it takes just one ill-advised tweet to provoke a Twitterstorm. Plus it’s all too easy for an off-target Facebook post to go viral for all the wrong reasons.

The last thing you need is for the trolls to pounce, trashing your client’s name in the process. So, it’s important to agree and document tone, style and content for social media beforehand – especially if your client has handed you control of their accounts.

Sticking to the agreed brief will help you avoid any potential flashpoints. And if you ever have to think twice about whether or not to post, either run it by your client first, or don’t do it at all. Better to be safe than sorry where Twitter & co are concerned.

Equally important if you have direct access to your client’s account is to keep it entirely separate from your own. The internet is full of stories of hapless tweeters posting their drunken ramblings to their client’s account by mistake.

If your client takes anything you put out on social media badly, or thinks it’s tarnished their image, it can lead to a claim.

Cover your back

Inevitably, you can’t always anticipate mistakes. Sometimes bad stuff happens despite your very best efforts. A curveball is thrown, it hits you square on, and you’re left reeling.

But what you can do is prepare for it.

Professional indemnity insurance for copywriters offers hard and fast business protection. It helps by providing legal expertise to fight your corner if there’s a claim against you, and by picking up the tab for any costs and compensation.

That means you avoid having to spend time and money finding a solicitor or becoming your own legal expert – because even if the claim isn’t justified, you’ll still have to deal with it. Meantime you get to keep running your business.

Sarah Adams is copywriters’ insurance expert at PolicyBee, a ProCopywriters partner and sponsor of The Copywriting Conference. Tel. 0345 222 5370