Keep other people's business cards with you at all times when you're out and about. Carry multiple (2 to 4) business cards of your most recommendable contacts. This simple tip pays off many ways.
For example if you always have cards handy for people in related fields or people your clients typically seek, it's a five-way win:
1. The person who needs the service or product gets a legible card with good contact info.
2. The person whose card you give out has a very good potential client who has already been somewhat pre-sold and roughly pre-qualified (it helps no one if you give a card for a Rolls Royce dealer to a new grad looking for a commuter car).
3. You get to be seen as a resource (by the person to whom you give the card).
4. You get to be seen as a good referral source (to the person who card you give).
5. You get time. You don't have to remember to get back to the person with the contact info (though there are times when that might be a better strategy because it gives you a reason to make another contact).
Don't allow yourself to dismiss this tip as too much hassle or bother or "too much like work". A system of carrying others' business cards is easy to set up and maintain and the payoff can be huge for all concerned.