Investment involves tricky choices. The starting point should be setting your long-term goals, writes John McCrone.

Investing is a series of dilemmas. Whenever you think about doing one thing, the exact opposite usually sounds logical, too.

Focus or diversify? Hire an expert or take charge yourself? Play safe or play the field? Keep it simple or get sophisticated? Time it carefully or just plunge in?

Choice after choice. It is easy to end up like Buridan's ass, the philosopher's beast that found itself placed exactly between two equal-sized stacks of hay and so starved to death from indecision.

To help out, here is a guide to the investment maze with its many forking paths.

Your first dilemma is whether even to save!

The starting point for all financial planning should be your long-term goals. How big a nest egg do you actually need? Once you have a figure in mind, then you can work your way backward.

A rough rule of thumb here is that for every $10,000 in salary you are used to, you could do with $100,000 in savings in retirement.

New Zealand superannuation, at $22,000 a year for couples and $14,400 for single people, reduces the burden for lower-income earners.

So you set your goal. And everyone knows the key to saving is to start young.

This is because of the miracle of compound growth. If you invest $10,000 at 25, then by the time you are 65, at a modest interest rate of 6 per cent, it will have turned into $103,000 (in inflation-adjusted dollars too).

But the same investment made at age 50 would only grow to $24,000.

Time counts with compounding because eventually it is your interest that is earning interest.

So clearly the earlier you begin your investing the better. Except, of course, there is the flipside to the argument.

If you have borrowed money on a student loan, a mortgage, or a clutch of credit cards, then your debts will also experience the "miracle" of compounding growth.

In these circumstances, every dollar spent to retire debt early is in fact a better use of any spare change.

The exception may be KiwiSaver, where government and employer contributions tip the balance the other way again.

Another part of the initial saving dilemma is insurance. How much of any surplus funds should go into life, house, medical, income protection, trauma, total disability, and other forms of insurance?

Trusts, wills and other kinds of legal protection are also an essential aspect of your "investment" planning.

Well, if you are now ready to do some actual saving, the next dilemma is whether to go DIY or pay for advice? There are good arguments both ways.

In the end, the only person you can really trust to look after your money is yourself. And who wants to pay fees to a middleman?

The harsh fact is that after inflation and taxes have been knocked off a healthy 10 per cent investment return, you are left with a rather more anaemic 5 per cent real return. Give away a couple more per cent to a financial planner and where does that leave you?

On the other hand, amateur investors can make costly amateur mistakes.

A balanced approach would be to pay an upfront fee of a few thousand dollars to a certified adviser to analyse your needs and draw up a plan of action. Then you can always shop around for the lowest-fee products that would serve this plan.

Now we can get down to the actual principles of investing. The most general dilemma here is whether to concentrate or diversify your assets.

The natural tendency is to put too many eggs in the one basket.

You will tend to focus on whatever it is you feel you know most about, whether it is rental properties, debentures or share funds.

And for investors with real expertise, concentrating your bets may even be the sensible approach. It is the only way to win big.

But talk to any competent financial planner and they should be able to convince you of the value of the portfolio approach.

You will be in enough different markets that a disaster in any one does not sink you.

Connected to the question of whether to concentrate or diversify is the need to balance risk against reward.

So a basic part of portfolio planning is to determine whether you should follow a conservative, balanced, or aggressive investment strategy. Simply put, the faster you need to grow your savings, the more risk you are going to have to swallow.

However, the advantage of a portfolio approach is precisely that you can calibrate your risk-taking to your eventual goal. The risk-reward equation used to have a more straightforward incarnation – stocks and bonds. You bought bonds for safety and shares for a return.

A bond is a loan you make a company or government in return for a fixed rate of interest. A stock is the purchase of a slice of a business and so you get a share of any profits. One is a promise, the other a hope, and they are priced accordingly.

The investment world has, of course, fragmented into every permutation of the old loan-versus-share distinction.

This has created the new dilemma of simple or complex?

Do you buy a heavily packaged deal, a structured product, derivative or hedge fund, the kind of deal wrapped up in impressive talk about collateralised debt, arbitrage opportunities and momentum strategies?

Or do you stick with plain, old-fashioned, brown-wrapper investment products where at least you feel you have a hope of understanding what it is you have actually bought?

Usually going along with the simple- versus-complex question is whether you prefer to invest naked or geared.

Most investors just invest dollars they own. But you can gear or leverage any investment by borrowing to get into the game.

The advantage is that gearing magnifies your wins. The flipside is why gearing should always present a dilemma. Leveraging a loss does not sound quite so smart.

Yet another standard dichotomy for the investor is active or passive?

An active investor is one who tries to beat the market. The passive investor instead just wants the average market return.

Most of the investment world is set up to encourage active investing. This is because it justifies charging a higher fee.

If a fund manager or financial planner says they have the expertise to out-perform the rest, then naturally you should pay them more.

But research shows that beating the market over the long run is usually more a matter of luck than judgment.

The alternative is to follow the passive or index tracking route. The idea is to buy the spread of any particular market – a little piece of every company in some index – then simply go with the flow.

Over time, markets generally rise. And because a passive approach demands no expertise, no active choices, investment fees should be halved at least.

It is these kinds of dilemmas which can make investing so daunting.

The better route is to accept that investment is going to be a series of dilemmas. Take a systematic approach and you should be able to knock them off one by one.