Anyone reading this thinking that I'm about to give you the magic formula for writing a great wedding speech is going to be a little disappointed but I can give you some advice which WILL save you a lot of stress, trauma and sleepless nights. It's very simple: start now.
As a wedding speech writer I work with people from all over the world, from all walks of life, every ethnicity and religion, and they all have one thing in common - they all leave it until the last minute. From the moment most guys propose they simply put off thinking about the speech, deluding themselves it's just a case of thanking the parents and saying how much they love their new wife. And for most Best Men, they remain resolutely in denial about the impending speech, convinced that they're caught in some kind of virtual reality nightmare, from which they will soon emerge, blissfully carefree. These scenarios are not the exceptions; they are the rule. And both groups are doomed to failure.
You cannot wing a wedding speech unless you are an exceptional talent, and most of the guys I speak are very talented individuals, just not the bit where it comes to standing up and making people laugh for ten minutes. The Grooms will realise halfway through their speech that little dissolves the mind and will to live more than listening to one million thank you's and some gentle sobbing. You have to think of your guests, these are the people you're communicating to because they are the ones whose imagination and interest you have to capture and that requires planning, development and writing, lots of writing. Success, for the average Best Man, cannot be achieved with less than a week to go unless they have professional help, because they simply don't have the time to make their speech all it needs to be.
So, my advice is to start now. Ok, it's January, but it will soon be Easter and then you're only a few weeks from the summer. Believe me - the time will disappear. I speak week in, week out to guys who have left it until the very last minute, sometimes the day they're actually meant to be giving the speech. All of them are terrified, all of them wish they'd started it sooner, and none of them are in the frame of mind where they can actually say their own name confidently, let alone a ten minute speech.
Give yourself a break, start thinking about the speech now. Either you'll give yourself enough time to write a cracker, or you'll find out that speech writing isn't for you, and you've given yourself enough time to commission a speech and have it well and truly nailed for the big day.