As I write, the S&P/ASX 200 (Index: ^AXJO) (ASX: XJO) has plunged 3.3% and where it will end no-one knows.

Put that down to the fact that Donald Trump has taken a slim lead in the US election over the pre-election favourite Hillary Clinton.

Brexit part II coming up it seems.

But no matter what the market is doing, Foolish investors need to keep their heads.

Don’t sell out. Don’t panic.

It doesn’t matter that Macquarie Group Ltd (ASX: MQG) is down 6.6%. Or that miners BHP Billiton Limited (ASX: BHP) and Rio Tinto Limited (ASX: RIO) are down 4.4% and 3.9% respectively.

And there’s simply one reason for that. Despite the prospect of the next US president being Donald Trump, the impact he has if elected are unlikely to be that bad.

There’s also still plenty of time left for votes to be counted and Mrs Clinton to retake the lead. And if I had to make a bet on the outcome, I’d still be betting on a Clinton win.

If that occurs, you can expect to see our markets reverse course and recover most, if not all of the losses we are seeing so far today.

We could even see our market swing into positive territory by the end of today if results go Mrs Clinton’s way.

Investors also need to remember that even after Brexit, our markets recovered as they had time to digest the news.

Selling out now more than likely means crystallising losses, and missing out on the recovery.

So what should investors do?

Turn the market off, stop looking at your portfolio, go and do something else and hold on tight. In a year’s time, we’ll probably look back on this day as just another blip, and there will be something newer to worry about.

What am I doing?

Not looking at my portfolios for one. Watching those stocks and companies that were too expensive to add to my portfolio before and hoping for a good entry price.

The one thing I definitely won’t be doing is buying shares in gold miners.

These Low Interest Rates Could Totally Devastate Your Retirement!

With global interest rates set to remain at these "emergency low" levels for years -- perhaps even decades -- unless you take decisive action NOW, your retirement could be seriously at risk. Click here to learn how to NOT run out of money in retirement.

HOT OFF THE PRESSES: Motley Fool’s #1 Dividend Pick for 2017!

With its shares up 155% in just the last five years, this ‘under the radar’ consumer favourite is both a hot growth stock AND our expert’s #1 dividend pick for 2017. Now we’re pulling back the curtain for you... And all you have to do to discover the name, code and a full analysis is enter your email below!

Simply enter your email now to receive your copy of our brand-new FREE report, “The Motley Fool’s Top Dividend Stock for 2017.”

By clicking this button, you agree to our Terms of Service and Privacy Policy. We will use your email address only to keep you informed about updates to our website and about other products and services we think might interest you. You can unsubscribe from Take Stock at anytime. Please refer to our https://www.fool.com.au/financial-services-guide">Financial Services Guide (FSG) for more information.

Motley Fool writer/analyst Mike King doesn't own shares in any companies mentioned. You can follow Mike on Twitter @TMFKinga

The Motley Fool Australia has no position in any of the stocks mentioned. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy. This article contains general investment advice only (under AFSL 400691). Authorised by Bruce Jackson.