You're a bloke. Your mates are blokes. Your best mate, the groom, is by definition a bloke.
Blokes are good at lots of things. They can mount shelves, assemble flat-pack furniture, and sink a pint quicker than a McLaren F1 can go from 0-60…
On the other hand, many highly capable and rugged males crumble when forced to express complex emotions. Unfortunately for you, if you fall into that category, your best man's speech is expected to dig deeper than the one-liners and traditional toasts. On your friend's wedding day, you are his chief character witness, presenting to a jury of new relatives an image that may be all they have of him until Auntie Doris's funeral in a couple of years' time.
For the emotionally inward best man, there are two hurdles to overcome; language and delivery. In the first place, you need to adequately convey the bond you share with the groom. In the second, you need to get your message across sincerely, without sounding like you're delivering his eulogy. Here are a couple of key areas where you can up your emo-factor without coming across like a big girl's blouse:
Memories …
If you've known the groom for a long time - since childhood, adolescence or college - dig into the past for a funny or warm introduction to your friendship. Everyone likes a bit of nostalgia and conjuring childhood scenes in particular will warm the cockles of their hearts.
Be careful, though, to use language that keeps your reminiscences grounded in the present. "John and I have been mates since I beat him in the sack race at our Infant School Sports Day …" is a line that does the trick nicely. It reminds the audience that your friendship is going strong, before time-travelling back to an instantly recognizable and friendly scene. Compare that sentence to the same basic opening gambit, delivered slightly differently:
The scene is the same, but the tone is less relaxed, and there's something about the conscious act of "remembering" that is distinctly funereal. You half expect the next line to be " … he was so full of life back then (sob), before the accident."
Praise him …
Unless you're on a mercy mission for a complete and utter Billy-no-mates, there will be things that you genuinely like - perhaps even admire - about the groom. Today, you have a license to say those things out loud without denting your manly image. Seize the opportunity. It's good for your soul; good for your friendship; good for your speech. That said, always remember where you are. Some of the groom's finer attributes may not be appropriate subject matter for a wedding crowd:
And if you really can't bring yourself to bear you innermost feelings to a packed reception, mask them with humour. They'll never know how much you really love him …