"Best Practices" differ based on your own experiences, what your comfortable doing, and what your environment is. When Symantec creates best-practice docs, they involve how the software was designed from our perspective relative to how we think a good network should be built. Obviously, that wont fit every scenario. There are, however, a few given that, if you don't do them, well, it'll catch up with you.
1) Having a Lab. Simply put, how can you know if a best practice, or any practice, will work for you if you don't test it? It's really a scary thing we hear about quite often when someone tries something for the first time in production and break everything.
2) Making Backups. <sigh> I don't know how to say this more, but if you upgrade your production environment without a backup, or purge some SQL tables without a backup... I just don't know what to say. Our current fav was a call the other day from someone with a hard drive failure that wanted us to recover the data. Nice wish I'll admit, but seriously, if you have a backup plan, you'll be better off. We have some pretty nice software for that BTW at Symantec called Backup Exec... (shameless plug)
3) Searching the KB, or at least Google. Save yourself a lot of time and grief.
From there, we'll try to help get you started with our best practice guides, but you'll eventually have to make your own. Ultimately, there are pros and cons to nearly every practice out there, and what will work for you WILL ultimately be different than for nearly everyone else.
GL everyone!!