I'm a DIY investor in my 20s: the mistakes and lessons I have learnt

As an investment journalist I felt it was important to align my interests with those of readers; but along the way I've learnt some lessons that novice investors all too often make.

It is worth pointing out that I am at an advantage compared to other first-timers, given that my day job is to write about investment and this involves regularly speaking to and reading the views of professional investors.

Note: funds with a star* are Moneywise First 50 funds.

How I have fared so far

Three years on from my first foray into the world of investment, my portfolio (which contains four funds and an investment trust) is up 30%.

Over the same time period the FTSE All Share is up 15%, while the FTSE 100 has gained 13% (after dividends have been reinvested).

But the FTSE World ex UK index has fared much better, up 40%. If I had pumped all my money into a cheap global tracker fund three years ago, my Isa would be bigger today. Hindsight is a wonderful thing.

However, my thinking three years ago was that, by definition, global tracker funds have a big weighting to the US stock market, around 55%. It is starting to become a bit of a tired argument, but three years ago the US stock market looked expensive and today it looks even more so.

I have no idea, and neither do any of the professionals, whether or when this will lead to a stock market correction, but I would sooner 'buy low' rather than 'buy high'.

With this in mind I decided to allocate a third of my Isa to the emerging markets. The two funds I picked - Stewart Investors Asia Pacific Leaders* and Aberdeen Global Asian Smaller Companies - have both served me well.

I have to admit I was pretty lucky in terms of timing: three years ago emerging markets were deeply out of favour, but in 2016 they have returned to form.

I am young and investing for the long term, so have time on my side to ride out the inevitable volatility that comes with investing in these less economically mature economies, in pursuit of higher returns.

The rest of my Isa is split between two global funds - Fundsmith Equity* and Scottish Mortgage* - while the remainder is in a UK fund, Marlborough Special Situations.

The mistakes I have made and lessons learnt

As an investment journalist I really should be practising everything I preach, but one thing I have not been very good at is rebalancing - which involves selling the winners and topping up investments that have underperformed.

Fundsmith Equity, for example, has been the strongest performer in my Isa and as a result has become a much bigger percentage of my overall portfolio.

Therefore, in theory I should perhaps have rebalanced at the start of this year and put the proceeds into the two emerging market funds, which had unperformed my other investments.

But I didn't, and I still haven't taken any profits. One of the mistakes a DIY investor commonly makes is running winners for far too long, and I am fully aware that not taking profits will in an all likelihood come back to haunt me at some point - but my thinking is that despite the strong performance my portfolio is not overly exposed to Fundsmith Equity, so for the time being I am not going do anything.

If I had invested in something specialist, say a biotech fund for example, I would not have hesitated to rebalance.

But the biggest mistake I have made is investing in something I didn't fully understand, which taught me to stick to investments that I understand thoroughly. I viewed the investment (a hedge fund available to retail investors) as a bit of a punt, so thankfully didn't end losing my shirt.

At the time I should have followed the wise words of Peter Lynch, who ran the successful Fidelity Magellan fund. Lynch's advice to investors was to "invest in what you know".

Other mistakes DIY investors make include obsessing over short-term performance, which can lead to unnecessary tinkering. Another common error is buying whatever is fashionable.

First time investor? Get in touch

If you have a question about where to put your money, you can get in touch with the investment doctor. Simply write to editor@moneywise.co.uk.

This article was originally written for our sister magazine, Money Observer.