Mark Stuart: Frankly, Mr Miliband, it's time to seize the opportunity... and watch your back

I know you've only been leader of the Labour Party for a few months, but people are already starting to mutter about your leadership. Of course, I don't share their concerns, but as a candid friend perhaps I can offer you 10 useful pieces of advice:

First of all, regain permission to be heard: the voters gave your party a kicking at the general election in May, and you will have to serve a bit of a penance until they forgive you. The only way you can regain their trust is to start talking about issues that the party failed to address in government, particularly on immigration.

Second, raise your profile. I know you've been experiencing the joys of being a new dad, but most people still aren't able to tell the pollsters you are Leader of the Opposition. Even someone supposedly as well known as William Hague only had an 84 per cent recognition rate after two years as Tory leader.

Having said that, my third piece of advice is not to engage in a series of ill-thought out policy statements. Don't fall into Hague's trap of having a plethora of policy announcements, but with no clear vision of where the party is headed. You'll just get accused of being opportunistic. Instead, engage in a major policy review along the lines of Tony Blair from 1994-1997 and Cameron, 2005-2007. Take your time to get the policies right.

While your policies are being formulated, seize the opportunity to reform your party's method for electing its leader. It cannot be right that the unions have an equal share in your complex electoral college system. Shift the balance away from the unions and towards ordinary Labour party members. I know that such reforms might make you seem illegitimate, since you were elected on the back of trade union votes, but it would show the electorate that Labour is willing to change with the times. Who knows, it might end up being another "clause IV" moment, echoing the changes made by Tony Blair in 1995.

Follow Tony by taking on the Left of your party. The genius of Blair was to realise that Left-wingers are nearly always incapable of getting their act together, so you can win a lot of brownie points with the voters by whacking them over the head a bit. It worked for Neil Kinnock after his famous attack on Militant in 1985. Why not start with Len McCluskey, the new extremist head of the Unite union: condemn any strikes if they are called.

Re-build your membership from the base. During your long period in government, the Labour party lost tens of thousands of members. Attract a broader cross-section of people back into the fold, showing that you are the party of real change. Take a risk by supporting next year's referendum on the Alternative Vote. I know your party is badly split on the issue, but supporting reform of the voting system might help you construct a rainbow coalition on the centre left – rather like Barack Obama did in the United States – which is capable of regaining power.

Be a constructive Opposition. There is no point in engaging in reflex attacks on Coalition policies, especially on the cuts. If you engage in Opposition for Opposition's sake, you will pay for it as the next general election nears: the people will not see you as a credible Government-in-waiting.

Get a public speaking coach for Prime Minister's Questions. I know David Cameron is at the top of his game, and is a master at the Dispatch Box, but apart from a couple of occasions, you've been lamentable.

Remember, performance is a huge part of being Leader of the Opposition. The Labour Party has little prospect of returning to power for over four years. In order to keep the morale of the Parliamentary Labour Party going, you need to up your game on a Wednesday lunchtime, otherwise the knives will start sharpening.

Your party badly needs a narrative. No modern political party can get anywhere without a clear narrative or story that they can sell to the electorate. My own view is that Labour needs to say the coalition is stuffed full of people from privileged backgrounds who do not have a clue about what ordinary voters are experiencing. Unfortunately, the leader needs to fit the narrative. With that in mind, my last piece of advice is that if, after two years, it is clearly not working out, be prepared to stand down as leader for the good of the party. If it is to win the next General Election then Labour must appeal to those voters, especially in the South East of England who deserted the party in their droves.

I know Labour is notorious for putting up with poorly performing leaders (Neil Kinnock and Gordon Brown being good examples), but make a ruthless self-assessment of whether or not you are a future Prime Minister. Sadly, your elder brother David, had that Prime Minister-in-waiting quality about him which you seem to lack.

Oops, sorry for mentioning the brother thing, and apologies for being so frank with you. May I take this opportunity to wish you a successful 2011? And if I may just sneak in one further piece of advice: watch your back.

Best wishes, Mark

Mark Stuart is a political historian from York who has written the biographies of John Smith and Douglas Hurd.