First and foremost. The quality of the source material is paramount!
Granted there are some tricks & technics you can use to improve something, do not ever start a session thinking you can fix it later! This is a big mistake, way to many engineers do ( Not just, new engineers suffer from this, old timers as well, Due to laziness)
Take the time to get to know what the band is trying to achieve. Do not just rush in and start setting up mics, do a quick mic check and start hitting that record button. With out, finding out what kind of drum sound they are looking for, do like wise for every instrument in the group. Also find out what they envision there album or demo to sound like. If you do not do this, you will be wasting a lot of time in setup,tracking and in the final mix stages of the project, in turn wasting the bands time and hard earned money. Not to mention how much a headache it will be for you.
For instance even at the risk of offending, always make sure the drummer is in Tune! and that also means in tune with the song. You can only pull so much 200, and 500 out of a drum sound before it starts to sound very un-natural. Not to mention, it will sound very "hollow" and with out the "power" normally associated with drums.
When it comes to Micing Drums, first rule is always to take your time, find that sweet spot before touching the EQ. There are many theories behind the perfect drum Micing technique, if you know them try them all before moving to the next drum. This is where that info you got at the beginning of the session comes in handy. If you know what kind of drum sound they are looking for, you will have an idea of what mics to use and what techniques to implement before the drummer even sets up. Speeding the process up. Also key here is, to watch at how the drummer plays his drums.
Guitars,, again this is where that info at the beginning plays in heavy, you do not want to put a Sure SM81 in front of a Marshall combo that is going to cranked to 11! it will not be a desired effect. Nor the trusted SM57, in many cases it does not lend it self well to extremely heavy bands.
Bass,,, 99% of the time they will be direct,, as to what direct box is used, plays a strong role in what "sound" is trying to be emulated. the Direct box in this issue is about as opinionated as the guitar amp is. Only suggestion here, is listen to as many as you can, find the ones that stick out in your mind,, and always if posable, carry a number of deferent types.
Keyboards,,Keyboards are simple, like the bass, 99% of the time, will be direct to tape ( unless the keyboardist is using a Lesley or some other kind of acoustic effect)
Piano,,like Micing Drums and guitar,, is highly opinionated and has a lot of approaches,, knowing what the sound is going to be,, will be a huge aid.
Organs that use a Lesley or an amp,, can be miced with deferent approaches as well. Again, and you will never here me say this enough, pay attention to what the band wants to sound like at the end of the project.
Vocals,,This is more debated then the current Busch & Gore Contest! Listen to the vocalist sing, get an idea of what there natural timbre is. This will give you a starting point as to what mic to use. What style of music is being played will also be a major factor here.
One of the best advice I can give is, never rush to get the project done. if you do it will come back to byte you, If not immediately it will in the future. Bands liked to be listened to when it comes to their music, give them that opportunity, and you will find that they will be open to listen to your ideas as well. I hope this gives some kind of starting point for the beginner.
I will be giving more of a Discussion on all types of ways to achieve a sound or result. Feel free to ask away, and I will answer to the best of my knowledge. Just remember that there are no rules in this game just guide lines that are meant to be broken

-----
Joel Gette
Soundscape Digital