Being on the wrong side of 40, it is inevitable that planning for retirement dominates my thoughts when it comes to investing.

Even the prosaic setting of Ikea got me thinking about retirement after I had a chat with a staff member who does not look a day over 50 but is 75. She told me that she likes the work and it keeps her busy. The job is not too strenuous and brings in some spare cash.

Work keeps the mind active and contributes to an improved sense of well-being. But as much as we may wish to continue in our jobs, increasingly, that may not be an option as workplaces get downsized.

Even if there are jobs out there, it is not easy to find something that ticks all the boxes.

Someone who has done years of administrative work and been a fantastic personal assistant to a top chief executive officer, for example, may not find anything suitable after retirement. It is not immediately obvious how the ability to create PowerPoint presentations or sell different products across the world would be an asset in the post-retirement job market.

I have long ceased regretting that I had neither the foresight nor the technical ability to train as an electrician or a plumber, a move that would have secured my long-term financial future.

In addition to a longer life expectancy, what makes retirement planning more tricky are the paltry investment returns these days. Where once double-digit percentage returns were entirely attainable, anyone promising returns of that magnitude should now be quizzed with a hefty dose of scepticism.

A quick run-through of the maths shows how challenging it can be to live within one's means after retirement.

Those who turn 55 after Jan 1 this year and have the full retirement sum of $166,000 in their Central Provident Fund (CPF) account can look forward to a monthly payout of between $1,280 and $1,380 after they turn 65.

This monthly payout undoubtedly comes in handy but, realistically, it is unlikely to be sufficient for those used to a middle-income lifestyle.

A restaurant meal at a shopping mall can cost close to $50. A holiday, even nearby in Asia, will likely require a budget of over $1,000. Even my younger colleague Samuel Chan, who wrote recently about his Taiwan jaunt, had to work hard to keep his holiday spending at $800.

When I reach 65, I may be still young at heart but my bones may not relish the overnight bus trips and train rides that he describes.

Even if holidays are banished to a distant memory, what about the emergency expenses that crop up? The air-con conks out - that could cost a few hundred dollars to replace. The washing machine goes on the blink - that is another few hundred dollars chipping away at the monthly budget.

What about presents at Christmas, and hongbao at Chinese New Year and weddings? These are bound to cause a spike in daily expenses.

So how would one go about bulking up this basic monthly sum?

One way would be to make whatever additional funds you may have work harder.

Assume you have a capital sum of $400,000. At Schroders, head of intermediary business (South-east Asia) Albert Tse suggests that this sum could be divided into two pots - one with a form of guaranteed returns, the other to seek higher returns by taking on more risk.

For the first pot, Schroders suggests that even after 55, when the mandatory total contribution falls from 37 per cent to 26 per cent for CPF members aged from 55 to 60, individuals should still maintain their 11.5 per cent contribution. This could boost returns, especially if these contributions are directed into the Special Account, he says.

The second pot - for achieving higher returns - could be invested in a multi-asset fund, Schroders says.

Here's another illustration on how to set the $400,000 to work.

The Sunday Times has been running a Save & Invest Portfolio Series that features simulated portfolios. The Singapore Exchange, CFA Society Singapore and national financial education programme MoneySense are behind the series.

Take the theoretical portfolio for the retiree based on an initial sum of $400,000. The allocation is about 30 per cent to Singapore stocks, 10 per cent to real estate investment trusts (Reits), 10 per cent to global exchange-traded funds and 50 per cent to bonds. The Singapore stocks are giving a dividend yield of 3.4 per cent, the Reits are yielding 5.5 per cent, while the bond yields give between 1.3 per cent and 5 per cent. Overall, the portfolio is earning a return of over 3 per cent.

Based on this figure of 3 per cent, assuming the returns are withdrawn, this works out to about $12,000 a year or about $1,000 a month.

Added to the $1,300 monthly payout from the CPF retirement sum, this gives a more comfortable sum of $2,300 a month.

The shares in the portfolio include those of local banks DBS Group Holdings and OCBC, bourse operator Singapore Exchange, as well as Singtel and Venture Corp. He has some exchange-traded funds, as well as Reits such as Ascendas Reit, which holds property, and Keppel DC Reit, which owns data centres.

The monthly $2,300 figure is a conservative one as the individual may have other sources of income such as rent from an investment property, or the money that he can withdraw from the Supplementary Retirement Scheme if he had stashed some away earlier while working. Neither is the individual tapping his capital sum.

However, the assumption also is that the individual has more or less paid off his property and is not withdrawing further amounts from the CPF to pay off his loan. If this is not the case, it may be difficult to meet the current CPF retirement sum of $166,000.

Also, the example of the portfolio and its returns relates to an individual. For a couple, the amounts should be higher although not necessarily double. In any case, $400,000 is a tough enough sum to set aside at a time when a couple may have to fork out a large capital sum for their children's tertiary education. And of course, all bets are off if one partner is not working or if another loses his job.

For many, reaching the mid-century mark is not necessarily an occasion for celebration but one of trepidation, as there is less job security and even less time to amass any meaningful capital sum.

The important thing, however, is not to panic. There are people who would be able to get by after retirement if they downgraded from their property, for example, or ran down their capital sum without leaving the children a single cent.

But quite often, these people who already have a few hundred thousand dollars in hand decide to put all of it into risky penny stocks, or choose to believe the relative who is marketing that investment plot of land in the US that will deliver a 20 per cent return within a year.

For myself, I think the best solution is simply to try to save more. Perhaps you may disagree. How is your retirement journey going? All views are welcome.