Invitation details?

Do you have a hotel room block? If so, I would include a details card with that info. Also put info on there telling your guests how/when to RSVP by. I would put the attire info on your website.

On the invite itself, you list date, location with address and time, and say 'reception to follow'. On a separate details card you list reception address if it is held elsewhere and list the website if it isn't on your save the dates. Hotel information and a map with directions are usually their own cards. Registry info is not listed anywhere, nor is dress code.

I put a map of directions on mine

The invitation should first say who is hosting the event (wedding) and what it is.

Examples:

"Mr. and Mrs. Jessilyn's Parents and Mr. and Mrs. Fiancé's Parents request the pleasure of your company at the marriage of Jessilyn and Fiancé"
"Together with their families Jessilyn and Fiancé invite you to their wedding"
"Jessilyn and Fiancé are getting married!"
Then put the time, date and address for the ceremony. If the reception is at the same place, just put "reception to follow."If the reception is at a different location, put "reception to follow at" and put the time and address.
If your dress code is black tie, you can put that in the bottom right corner of the invitation, if it's anything else, just put it on your website.
If you're doing physical RSVPs, you would put that on a separate card with a stamp if it's a postcard, or a small envelope with a stamp if it's not.
You should also include a details card since you want to include your wedding website. If you're
Ours say, something like "A block of rooms has been reserved at [hotel name] for your convenience. To book your stay and for other details relating to our wedding, please visit our website [wedding website URL]."
If you're doing online only RSVPs, yours could say, "please RSVP by going to our website."

I would suggest looking up some samples or templates! But I think basically the following:

date, time, location

wedding wedding where they can find more details about the events

deadlines

contact information (usually an email)

Where are you ordering them from? Most online retailers have templates where you just enter the information. They should be able to guide you easily

I am DIYing mine as well! So I have the actual invite with the usual info- date, start time and address, then I have the accommodations page, RSVP page and the “additional deets” page with the arrival time, attire info etc

I agree with the above but it has been done where you can dictate attire directly on the invite on the bottom right hand corner. That's what I did. Or you can even put it on a reception card if you have one.