Cold emailing often reminds me of my favorite outdoor sport--fishing. As the daughter of a retired fish biologist, I've been fishing since I could barely walk.

To catch a lobster or hook a trout, you need two entirely different approaches: setting a trap or dangling a nightcrawler on a hook, respectively. Catching a bass? Make sure you have the correct bait for the season and don't fish right after a storm, which is the worst time to catch bass.

Likewise, with email campaigns, there are many types of sales tactics to account for the wide variety of "bait," or selling techniques, that appeal to different audiences. Are your potential buyers driven by a little fear or do they find motivation in success stories? Do they just want to see numbers?

You don't want the wrong approach to ruin a perfectly good sales lead. With that in mind, here are some tips from the world of fishing that will help you send the right message to potential clients.

1. Know what bait to use.

Nightcrawlers may be the traditional bait for trout, but depending upon where and when you fish, you may have better luck with salmon eggs. That said, scented marshmallows are hugely popular in certain types of trout-fishing environments. Most of us wouldn't have guessed that on our own--it's the research prior to the fishing trip that lets us determine the bait.

That same premise holds true for email messaging. You can A/B test all day long, but if you haven't done your research, you could waste a lot of time trying out techniques that aren't remotely appropriate for the audience.

Start by identifying the buyer's job, industry, and other basic intel. Even things like geographical location and company size matter. Then, consider which of your company's benefits your potential clients respond to. Do enterprise-software companies really like statistics or are they more likely to read an email that quotes an "expert" influencer? Do managers at small companies want competitor news or does it paralyze them with fear?

2. A/B test the waters.

Maybe you have a theory that salmon really love gummy worms. (Believe it or not, people actually try this.) Intriguing as that idea sounds, there's a high possibility that salmon don't, in fact, respond well to candy, and so setting out in a boat with that as your only bait would put your whole fishing trip in jeopardy.

In the same way, don't assume that all technology companies respond to statistics or that name-dropping celebrities is the best way to reach all C-level executives. Instead, test a few different kinds of "bait" to see what works. Rather than blast your entire list of contacts with a single approach, divide it into two samples and test different emails against each other.

For example, try one email that uses a fear approach against another that demonstrates value. Or test a qualitative example against a quantitative one. By examining the open and response rates to different email strategies, you can determine which approach works best for that particular type of buyer.

3. Pace yourself--patiently.

You never know when external factors might affect your sales emails. Perhaps you sent a cold email to someone who went on vacation but forgot to set an autoresponder. Don't give up after a couple emails just because of the silence. Just as fishing often requires hours, if not days, of waiting, it may also take time and multiple emails to get a response to your sales emails. And if one approach doesn't work, try a couple more. This is why having the right targeted approach and A/B testing are so important.

Once you know what works, you can use it to bring in an even bigger haul. Scale up: if you emailed 100 marketing directors and found that one approach worked, try it on 500 marketing directors, or 1,000. (Just be careful with scaling up your volume too fast so that you don't harm your email deliverability.) You can also apply your learnings from the results of your email campaigns to other aspects of your business, like your website or blog, and use them to lure even more leads.

On a final note, be open to changing up your bait every now and then. New technologies and changing markets will inevitably lead to different sales techniques over time, and what's seen as a best practice today might be antiquated in a year. Plan, and fish, accordingly.