Let me start by saying unsurprisingly I don't follow rules when it comes to weddings - so this isn't going to be a post about what you should do when it comes to your wedding stationery.
However, if you are an invitation rookie like myself here are some practical tips:
1) Factor in thank you cards into your stationery order. Get enough card, paper and envelopes for both if you are going the DIY route. (If you are working with a designer or buying kits these often also include place cards, menus, RSVPs, info cards and other pieces I have forgotten.) If you are also wanting to do these factor enough card etc to cover everything.
2) Don't forget a little blurb about RSVP. In my opinion there is absolutely no need to include an envelope. I am pretty confident our guests know how to email, call or text. So no, we wont have a stamped return mini envelope. (Hot damn we are such rebels.)
3) Save the dates. Take it or leave it in my opinion. Having said that I have to respect that our guests wont be placing the invitation in a frame on their mantelpiece - so it is definitely possible an invite could get lost, especially if you want to send it with plenty of notice. (When I say 'our guests' I mean everyone aside from my mum, who will have our invitation on the fridge for the next 25 years right next to that freaking horrendous passport photo from 2000, that I turn around every time I visit. )
4) It's perfectly ok to just do things your way. I designed our invites and they are completely wedding formula free. They also don't contain a wedding font nor any mention of gift registry, map, handy hints or any other extra bits of paper. Zero calligraphy. Again rebellious as hell however, I am pretty sure that our guests will be able to figure things out - without the 5 extra lace edged bits of paper.
5) Time frame - do whatever works. However, general protocol says save the date's are sent out 8-10months in advance and then the invites around 8-10 weeks in advance. Don't quote me though as my eyes glazed over when I looked that information up.
6) Themes. If you have read my previous post on themes you will probably know what I am about to say...If you want to be super thematic maybe think about adding an element of that into your invitations. I read somewhere that coloured paper and a modern font screams backyard wedding and calligraphy is a more formal occasion. I then moved on and made our invitations according to what worked for me visually. Such a badass.