How - exactly - do I get a new domain to point to an existing domain?

I have had a website (www.ExchangingRings.com) for over a year and my advertising for it is already successful. However, I've added services beyond the scope of the original domain name (which is, unfortunately self-limiting), but don't want to rebrand everything. 

SO... I just bought a second domain (www.RitualRabbi.com) that I'll be using in my new advertising. When people type in the new website name, I want it to automatically go to my current/old website. I do NOT want to build a whole new website. I just want the NEW domain to automatically point to the OLD domain. I can't figure out where (and exactly HOW) to do this. A step-by-step guide would be much appreciated.

I hope I've explained this well enough for folks to know what I'm trying to do.

THANKS for any help you can offer.

@ExchangingRings This is totally doable! We can add your new domain and make it the primary domain. 

Where did you buy your new domain from?

I still really want the original to be my main site. That's where I'll be doing all my website editing. In fact, NO website exists on the new domain. Most of my existing marketing will continue to point to that (old) page.

What I want is when someone enters my NEW domain name into their browser, it will automatically redirect them to the OLD page.

Both domains were purchased through Squarespace and reside there.

@ExchangingRings We can totally do that!

Step 1: Go to your account on Squarespace and at the top, click Domains.

Step 2: Find the domain you want to connect (www.RitualRabbi.com). Click on it, then Manage Domain Settings.

Step 3: This will open a dashboard for your domain. In the top right, click on Move Domain.

Step 4: A popup will appear, asking you to select your destination. There will be a preview of your site on the left, just like on your dashboard. Select the website you want to connect it to. Click Save.

Step 5: Squarespace will open the Domain page for that website and another popup will appear. It sometimes takes a few seconds, so if you don't see it right away. that's okay. It's ask for confirmation that you want to move it from (trial site url) to the website you selected. Click Confirm.

Step 6: A small white box should appear, letting you know "Your domain has been moved".

You should see it listed with your other domain. www.ExchangingRings.com should still say "primary" next to it. 

Two thoughts on this...

1) I tried to follow your clear instructions but instantly hit a snag. When I clicked on "Move Domain," I got the pop-up box, but all that appeared there was a small spinning black square. I tried this both in Chrome and in Firefox and couldn't get past that spinning square.

2) If I try going to the new domain, "www.RitualRabbi.com," (which doesn't have a website there) in my browser, it current automatically redirects to my original website, "www.ExchangingRings.com," which is fine, in concept. I'm not sure how that is happening, unless that's the default since I bought the new domain as a secondary domain within my Squarespace account and didn't build out a webpage for it to land on.

HOWEVER, I really want RitualRabbi.com to point to a specific page on my website (www.RitualRabbi.com/other-rituals). If there's a way to figure that out, that would be the end of this conversation. LOL

Thanks for coming on this journey with me.

Jeff