Artist Manager - Crucial Music
Play live as much as possible. Believe it or not, if you DO have something special, the industry WILL find you.
Don't send over-packaged promo material or 10 MB emails to people. A quick paragraph with a link to a track will work better, but don't hassle people for feedback. The industry is not a government service that exists to provide advice to musicians about their songs. We're all very busy. If someone hears your song and likes it, they will usually get in touch with you or respond. If not, keep practising and keep writing.
We are sometimes approached by bands who have written half a dozen songs and feel like they need management to move forward, but an emerging band is better off doing as much DIY as possible to "learn the ropes" and understand the industry.
I've come across bands who have done contracts with record companies or publishers before looking for a manager – perhaps to save having to pay a commission. Something to keep in mind is that a quality manager will earn more than the commission you pay them, negotiating a better deal for you.
So ideally, find a manager before you sign contracts, but just make sure you've got the right one. If you can't find the right one, then paying a good lawyer is also going to be a major plus.
A lot of the profile managers already have their hands full so there's a possibility you could end up as a low priority.
Someone who genuinely loves and believes in the band, and who you feel you can really trust, is ideal. Experience is great, but enthusiasm and asking lots of questions to learn can be just as good.
Keep an honest and open relationship. Keep it professional. There's no harm in being friendly, but I wouldn't suggest hanging out and having dinner every night. It's a working relationship, you're not meant to be best friends.
I like to say to my bands "My role is to do all the business and planning so you can focus on writing and creating." Like a team I guess. Basically the manager is the contact point between the artist and everyone else, be that label, publisher, booking agent, promoters, merch designers etc and its our job to keep the wheel turning.