Determine the overall arrangement and song structure in your head before you start.
The first decision is whether to use a live band, which prevailed during hip hop's first wave from 1979 to 1983, or to create a more complex atmosphere built around sampling, with other instruments layered on top. Have some ideas for vocal arrangements, which will go some way toward determining the finished musical track.
Run through the track before recording it--whether you are the talent, or someone else is doing the honors.
Everyone involved will benefit from a chance to work out potential rough spots ahead of time. Listen for vocal lines that do not mesh with the track, lyrics that sound awkward, or an overlong intro that kills momentum. The prevalence of home recording equipment has taken pressure off fledgling producers and provides an alternative to high-dollar studios. Don't let that be a reason, however, to skimp on pre-production, which is crucial to saving time and energy.
Begin with the drumbeat and the vocal hook, the two elements that do more than any other to define a hip hop track.
To some extent, the finished product will depend on whatever equipment you own or access, but the Alesis SR-16 and Roland 808 have remained among the most-popular drum machines. Lay down a rough rhythm and vocal--known as a "scratch track"--to start building the track. Do not worry about perfection at first because you can always revisit the results in a multi-track setting.
Add other melodic instruments as you see fit.
Synthesizers rule the roost in most hip hop productions because it makes hundreds of rhythmic and tonal choices available at the push of a button, eliminating the need for hiring a cast of studio musicians. Guitars and basses are equally popular to provide rhythmic punctuation, or the first wave "old school" style that groups like the Grammy Award-winning Roots have done so much to popularize. For even greater contrast, mix live instruments with their synthesized counterparts. This is why top producers like Dr. Dre or Timbaland keep drum kits around, for example, when the right feel is not forthcoming.
Stay conscious of how you want the finished track to sound throughout the recording process.
Think carefully about the impact of your production decisions. No matter how small, every choice is important. For example, condenser microphones tend to be costlier but more desirable for studio work, due to their wider range. Dynamic microphones, on the other hand, are considered more durable, and less prone to distortion. Always think a step ahead when making these decisions, instead of taking a "fix it in the mix" attitude.
Consider carefully where your effects fit into the final mix, especially if you plan on using sequencers to trigger beats, or make samples into an integral part of the framework.
Regarding sampling, not every artist will feel flattered if you appropriate even a brief snippet of his recording--so either clear up the issue beforehand, or consider re-recording the part with a live musician, tweaking it enough to dissociate it from the original track. Alternatively, you may opt to create a totally new recording, using computer-generated beats if the digital audio workstation is your weapon of choice.