There is only one really important bit of advice I can think of for a beginner.
Never take anything as writ – do your research, find out as much as you can and make up your own mind.
I could really stop there because honestly, it’s the best advice I could give anyone. There is a habit of taking everything as writ – as being right, true and the one way (we all know the kinds who do) and it becomes limiting. Take the time to discover what you feel called to and explore it fully; this way you’ll build your own path instead of an imitation of some one else’s.
And because I’m on a roll:
Don’t let anyone tell you you’re doing it wrong – if it’s right for you that’s all that matters.
Never read only one book and think it is the answer – it rarely is.
Always know what you’re doing before performing any workings or rituals.
However spontaneous magic is a powerful thing as well. Do it often.
Don’t try to run before you can walk, you'll only trip up and face-plant.
Take your time, there’s no rush – walking this road is lifelong, you'll never learn everything there is to learn so enjoy the process.
Never ever presume to tell anyone else what they’re doing is wrong – especially if it is a more experienced witch – besides being rude, it might not end well for you.
If you love herbs, start with the easy ones – the more obscure and baneful ones are not for beginners (unless you have a death wish, then by all means).
Being new to the Craft is exciting, and some of us who have been on this journey longer don’t mind helping you out but don’t get shitty if we say no – sometimes we’re busy, have other things to do or prefer to keep our practice private. A sense of entitlement and expectation of obligation will not go over well.
If you want a magical name, then choose one that suits but by all that is holy, please don’t run around calling yourself something like Lady Morrigan Faery Unicorn Glitter. Really. Don’t.
If television is your source for knowledge – please meet Google, it will be your friend.
Exception to above rule: Hocus Pocus. All Hail Queen Winnie.
Witches do magic for personal gain.
Not everyone follows the same path – some witches will hex, bind, curse, use bone or blood and do a multitude of other things. If you walk another road – awesome – but please bear that in mind while speaking on another’s Craft.
Shading magic is generally annoying (white/black/grey).
Always be respectful to other witches, if you respect others that respect will be given in turn.
Bouncy enthusiasm is great but when embracing the feeling of shouting your witchiness from the rooftops; check the temperature of those around you – they may not particularly be supportive.
Online forums are a great place to chat or meet new people – beware of the propensity for drama – it can get uglier than a pissed off wasp in a heartbeat.
Stuff is not necessary. Tis awfully nice to have but one can find oneself become somewhat of a hoarder without meaning to.
Always have good ventilation for incense burning.
Don’t go sticking people with your athame – it’s not the done thing.
Ouija boards – not a toy.
Never leave your candles unattended.
Never invoke, summon or invite that which you can’t banish (although, being a beginner, I have absolutely no idea why you’d be invoking, inviting or summoning anything – perhaps best not to attempt it).
And finally – and probably most importantly:
May your path be long, your journey be fruitful and your knowledge real and not from Sabrina or Charmed.