The beauty of studio shooting is that you have absolute control over every aspect of your final image. From makeup, to the general lack of ambient light to deal with, to the subject in front of your camera, everything is up to you. This can bring some challenges _ namely, you as the photographer are also the director of the entire shoot. If something isn't going right, it's your responsibility to fix it. I apply this to everything in life, but it's especially relevant in assembling a successful shoot. Remember the six Ps of life: proper planning prevents piss-poor performance.
You don't always need a professional model. If you have some new lighting setups that you want to try, ask a friend. Bribe them with free food and make sure they can be patient for an hour or so. For more complicated shoots involving heavy makeup/prosthetics or complex costumes, it might be best to contact an agency or an unsigned model friend that needs some new portfolio images. Make sure to communicate the idea with them well before the shoot so they understand their job. If you're not shooting portraits and are working with products, you're in luck: you can shoot to your heart's content.
Always draw out some lighting setups beforehand. If you have a piece of paper with a few general ideas with you to reference, it's much easier to make efficient use of your studio time, as you aren't trying to remember exact angles and ratios for your lights. Many of us photographers are horrible at drawing (I certainly am), so just create something crude. You could even write it down without a diagram if you feel uncomfortable about drawing. Of course, the lighting needs to match the theme, so don't just bring any setup you have drawn out. Light specifically for every shoot.
This should be obvious, but figure out which props you're bringing and their exact purpose. If you're using props for a paid gig, you will look like a fool if you're fumbling around on set trying to figure out how to incorporate them. It's okay to try different things and see what works, but a solid starting point is a must. I highly recommend including props in your gear list or lighting diagram as a better way to figure out their place in the final image. If you have a stylist, they will help tremendously with this and should be included in the planning process.
If you don't have your own space to use, make sure that you give yourself plenty of time. I'm fortunate enough to have access to my own space, so my setup time is cut down drastically by not having to bring stands, sandbags, and flags into the space each time I shoot. If you're renting a studio, budget an extra half-hour to forty-five minutes on each end for setup and tear-down. The last thing you want is to hold up the studio's next client by occupying the space for longer than you paid for, even if you are taking your equipment out as they bring theirs in.
Wardrobe and Makeup
These go hand-in-hand usually. In 95 percent of your shoots, the makeup and clothing will be in a very similar vein as far as texture, color, and style. For test shoots, I wouldn't expect most folks to have a makeup artist or stylist at every session. I highly recommend taking the time to brush up on some simple makeup techniques and to use Pinterest or Tumblr to gather images for inspiration. You just need to be able to clearly voice your vision to the model or to whomever is doing the makeup and assembling the wardrobe.
I love shooting in the studio and harnessing the complete freedom of it, but in the last year, I have learned a great deal about assembling a team that can work cohesively. Again, you are also the director of the shoot. If you are assembling the concept in tandem with other creatives, you need to be able to collaborate and express your thoughts to bring the idea to life through every aspect of planning. If you don't plan, you won't be using your time to its fullest potential.