You don’t pick an agent. They pick you.
Their job is to discover and nurture new writing talent, so they’re looking for what you can offer them.
Agents work for literary agencies large and small or operate as sole traders. Each agent can deal with a limited number of clients at any one time and may take on only a handful of new ones a year. So they can afford to be choosy.
Some don’t accept manuscripts unless they’ve been referred by, for example, an existing client. This means that the very best way to find an agent is to have a chum who’s already got one, who can introduce you. This is what happened to me. The result was my first book, Love Child.
I was lucky. Otherwise, research and determination can get you there.
There are over 100 agencies in London alone. The most comprehensive list is in the annual Writers’ and Artists’ Yearbook. Many specialise – for example in commercial fiction, children’s, TV tie-ins, or particular subject genres – so you need to whittle out those who match what you have to offer. Look at their websites and see who they represent. You might not be in their league (yet) but are they ‘your’ kind of writer?
When approaching agencies, be sure to give them what they ask for: a synopsis and two sample chapters is usual for fiction. They need to see a decent sample of your work. Expect rejections. Or silence.
But if a reputable agent takes you on, you’re on your way.