Helping guests find the venue?

Balloons would be better than lost guests. you could do something like the open house signs. Maybe tie yellow ribbons around old oak trees. You could possible get 4 foot high plant stakes and put a little flag on them. This depends a bit on the general location you are at. Some things may not be permissible.

Could make a sign to put out by the road. My venues driveway is obvious if you know it, but easy to miss if you're new to the area.
Our coordinator puts a sign out by the road. I think it says "it was always you" I don't care for it, but it helps guest to know where to turn.
Even if balloons are tacky who cares would rather have some tacky balloons then a bunch of late or missing guests.

They can actually do some pretty cool balloon installations for weddings! You could do something like this and it wouldn’t look like a kid’s birthday party

View Quoted Comment Yeah I think you're right. It's small enough of a detail (looks wise) that it doesn't matter but matters a lot in terms of guests actually finding the place

View Quoted Comment These look super cool! Maybe I could have something like this kind of arranged around the sign.

View Quoted Comment I think that would look great! I did find some examples of people who incorporated signs with the balloon installations

Those balloon displays are gorgeous, but even if you don’t want to pay for something that elaborate, I still think even a tacky bday display is better than nothing as long as it’s visible from the road. My friend’s wedding was at this amazing auction house venue, but from the outside it just looked like a deserted warehouse in the middle of a bunch of other warehouses and there was no signage. I was in from out of town and crashed with another friend who dropped me off, and she almost turned around and took me straight back to her place because we were like surely this cannot be what we’re looking for. We didn’t even feel safe! So any indication that we were in the right spot would’ve been so appreciated. It was GORGEOUS on the inside, though. 😂

I would use the balloons or add a sign out front. Better than people getting lost!

Please put something and make sure it is big enough and stands out enough so it is seen.
Went to a wedding once down some country backroad. The venue had no sign what so ever. All the couple put was a small cardboard sign. We drove past it, quite a bit, and had spotty cell service. It wasn’t a fun start to the event. And we arrived just minutes before the ceremony started because of it.

View Quoted Comment Yeah after reading all the comments I'm just going to get a nice bunch of balloons and a couple of those 36" ones to tie to the sign. The sign out in front of the venue isn't noticeable if you don't know to look for it, so I'm including directions on our website too but I think the big balloons will be necessary to draw more attention. I'd like to do something more attention grabbing but balloons are the best idea I think

You could try getting some tulle and ribbon in your wedding colors from a craft store and tying big bows to the sign. Glitter tulle and glittery ribbon could also work if they'd be likely to catch the light. Not sure what the sign looks like or how easy it would be to tie something to it, but maybe using command hooks or something could help if needed. You could also try looking up pew bow designs on Pinterest and seeing if there's anything that sparks your imagination. A lot of the ideas on Pinterest also have links to DIY them!

Definitely agree that balloons would be a great indicator as guests are pulling up closer!

Also, I would HIGHLY suggest going out to the venue and dropping a pin while you're standing exactly where they need to park and putting it on the directions page of your website as a link to apple/google maps.

OR even a little email blast with the dropped pin could work! It will put it on your guests radar that it is a bit tricky to locate and (hopefully) they'll take precautions to look up directions early and give themselves extra time to find it when they are driving out on the wedding day!