When you are in the process of building a pay-per-click advertising campaign, one of the least enjoyable but most important things to consider is your budget. How, in fact, do you intend to spend your (or your clients’) money?

The answer, as always: It depends. Are you a veteran online who is trying to drive a specific part of the business? Or are you a first-timer trying to find out what exactly happens in this untapped advertising medium? Do you have a thriving storefront business that you’re seeking to expand, or are you an online-only retailer dealing with razor-thin margins?

There’s lots to it, of course, but budgeting always starts with your basic strategy.

With these thoughts in mind, here are a few tactics to consider:

Budget by product line or service offered
Perhaps the most logical to first-time online advertisers, budgeting by product line is probably the easiest to conceptualize. This budgeting tactic involves the simple campaign strategy of devoting a campaign to each individual product line, and setting your daily budget accordingly. Because you have organized your account with product-specific campaigns, you will be able to easily check whether or not you are on track to hit your monthly spend goals or limits.

Budget by desired conversion
If you have a website that seeks to accomplish multiple things, you have a different type of budgeting task. There are many sites that seek to drive, for instance, “Contact us” form completions, online purchases, email newsletter subscriptions, and job applications. Each of these four elements impacts the business in a different and beneficial way.

To budget by desired conversion, then, pool your keywords into relevant groups by conversion type. From there, organize these keyword groups into separate campaigns and track your spend, similar to in the first option. You may run into difficulty here, as several keywords may have overlapping conversion possibilities.

Alternatively, you may consider “by landing page” rather than “by conversion” budgeting. Rather than adjusting keywords on a desired conversion-by-desired conversion basis, you could simply run the same keywords in each campaign, and use advanced dayparting options to focus spend on a different landing page according to the time of day.

In addition, if your company has separate business units or altogether separate budgets handling these tasks, you might want to go so far as to create completely independent online accounts.

Go where the traffic takes you
The most basic tactic is sometimes the best tactic. One budget. One campaign. Press “Go,” and see what happens. Rather than try to make the internet and a competitive online advertising space fit your motives, simply deal with the nature of the market. This is the easiest budgeting tactic, but probably the most harrowing.

It can be particularly helpful for new online advertisers, however, as high conversion rates can indicate your strengths relative to the rest of the online sphere, while high search-traffic terms can call attention to areas where you can expand and improve your business.

Another note on budgeting: I have always found that, at the outset of a campaign, you are better off operating with a full flow of water, rather than a trickle. Be aggressive, and let your keywords build quality score. As the month progresses, more carefully track your day-by-day spend to ensure that you are tracking towards your ultimate goal.

Also, as you set your daily budgets, always remember that, as a rule, weekends will see lower search and click traffic than weekdays. Therefore, never simply construct a monthly budget and divide by 30 to set your daily budget. Consider, instead, that you will probably spend about 80% of your budget from Monday through Friday, though this figure can vary drastically based on the contents of your site and the demographics of your target market.

Do you have any other budgeting tactics that you have used? We’d love to hear about them in the comments.