Whether you're a new CEO or a middle manager, what you do in your first 100 days establishes a precedent and creates a reputation - for good or bad - that can be hard to shake off. So how can you be more effective in your first 100 days?

Even if your mandate on joining an organisation is to deliver radical change and shake up an existing team, beware of acting too quickly. A major complaint made of newly arriving managers is that they pursue initiatives too hastily in an attempt to show that they are in charge - rather than observing, listening and learning.

Unless there is an immediate crisis to be tackled, understand that acting too quickly sends out the message that you know better than your new colleagues.

And that can ruffle feathers.

Start instead by spending time with your direct reports on a one-to-one basis and then with their direct reports in small groups. Ask their opinions; acknowledge their experience and expertise. Remember that the people who brought you into the role are probably far more removed from the customer than your reports and their reports.

A questioning approach and a touch of modesty will win you more respect and long-term buy-in than arriving full of ideas and all-conquering confidence.

Six good questions to ask include:

•    What do we need to start doing differently?

•    What do we need to stop doing?

•    What do we need to continue doing?

•    What would you like me to do?

•    What are you afraid I might do?

•    Not that I'm saying I will fix it, but what do you think my number one priority should be?

All organisations have political undercurrents, no matter how much the managers there may deny it. On paper, everyone may have signed up to do what is in the best interests of the organisation. But the reality is that your new colleagues will have personal as well as organisational goals in mind. And some of your colleagues will have substantially more sway and power to disrupt your efforts than others.

Spend time identifying the key stakeholders across the organisation that you absolutely must have on side. If, for example, your mandate could mean an encroachment on someone else's territory or a diminishment of their role, then get ready to spend a significant amount of your time winning them over. If there are disappointed colleagues who applied for the job you now have, be prepared to invest time and effort in neutralising their probable resentment towards you - or decide whether you may need to remove their disruptive influence from the team entirely.

No one likes to be told what to do. Your colleagues will want to feel consulted. So keep going back to key stakeholders who you must absolutely win over. Do it as much for the opportunity to build a relationship with them as for the actual information they may be able to impart. Even if you have decided how to proceed with the task of reinvigorating the team and organisation, at least make people feel that they have been listened to.

At the end of the day, your job is to deliver results. But don't mistake activity for productivity. Immediately initiating a dozen projects that will ultimately deliver value may introduce an uncomfortable level of change for people - especially if the projects have long lead times and do not deliver visible results quickly.

Seek to deliver a small number of quick wins if you can. A handful of early results can do much to build your credibility. At the same time, be careful that these quick wins do not undermine your long-term credibility.

For example, firing an underperforming member of the team would send a clear message out to the rest of the team. But you don't want others to question whether you should have tried coaching and supporting the individual first. Or encouraging the business to drop prices to shore up volumes may be appealing in the short run, but will it have the desired effects on long-term profitability?

But just as important as delivering quick wins is making sure that you communicate your successes. Contributions to the business that are not seen by the right people have little worth. So, especially in the early days, make sure that you spend as much time talking to people and communicating your successes as actually delivering them.

In an ideal world, it would be possible to dictate exactly what deliverables should be delivered and when. But that would be too simplistic. What a CEO needs to deliver in a small advertising firm will differ completely from what a regional manager needs to deliver in a global technology business.

But the principles remain the same - in terms of taking the time to learn about a culture, focusing on key relationships, and delivering quick wins.

So learn by the mistakes of other managers. Make your first 100 days memorable for all the right reasons.

Dr Rob Yeung is an executive coach at corporate psychology consultancy Talentspace. He is the author of over a dozen books including The Rules of Job Hunting and The Rules of Office Politics (Cyan/Marshall Cavendish).