Poster 10 was broken in an old update. It has since been fixed with the 'Happy Holidays' update (14/12/2017).

I know some people will be unhappy about the existence of this guide, as they'll believe it is better (or "fun") to find these collectables by ourselves without help. If you don't care and just want to have the achievement, then go ahead, all the information is here. But even if you don't agree with the idea of a guide, please note that you can always look first for the collectables, and once you've spent enough time on them, you can always come back here to see the location of the few you may have missed.

Please keep in mind English is only my third language. There are probably a few mistakes here and there (and keep in mind I use UK English), but many native English speakers make more mistakes on a daily basis than there are in this guide. If you're unhappy, next time I'll write it in Spanish. Or French.
This message may feel aggressive, but I've already had people using my level as an excuse for I-don't-know-what (attacks?). I do take feedback, so if there's something that could be improved (text-wise), leave a comment, I'm always trying to improve in languages in general :) .

Here are some useful tips and information you have to know before you start looking for the collectables.

First, decrease the foliage quality in your graphical settings from whatever you have it and set it to "Low". This will turn off most foliage and make it easier to spot what you're looking for.


Next, you need to know how these collectables look like. There are 4 different types of collectables along the route. You'll be looking for markers, hard hats, posters and signs. Some can be found easily, others will require some effort, as they'll be very well hidden behind buildings or they'll blend in with the environment. Just finding them is not enough. You'll have to walk up to them, and once you're close enough, the game will automatically award you the discovery. Markers will be placed back, hard hats disappear, a poster will appear on the white board and on the metal rod a sign will be put up.

Markers:


Hard Hats:


Posters:


Signs:



I recommend loading a service that runs during daytime, and, once in-game, not doing the service. You'll be using the engine to travel along the route, as sometimes there won't be any items for kilometres. Please note that there's no fast way of finding all the collectables. It's taken me over 30 hours and over 80 kilometres of walking to find all of them (and even with all the time spent, I still had to ask nickhawk for the location of the last marker, as I couldn't find it, so many thanks to him!), but with this guide you'll be able to find all of them in around 10 hours or so.

Knowing the route also helps. So if you're a new player, I recommend to first play the missions or do some services, otherwise you may get lost.

While driving slowly, use camera 8+Arrow Keys to check the sides of the track. In case you want to go faster, you can use Shift+Arrow Keys while on camera 8 to fly around the map relatively fast (you'll understand once you try it....).

This guide is divided in four main sections: Hard Hats, Markers, Signs and Posters. In each section, you'll find a main map with all 25 locations, and for each collectible, you'll find a screenshot of what you're looking for plus the exact location on the map.

First of all, this is what you're looking for:


These sticks are mainly found near crossings, so keep your eyes open when near them. They will be laying down. You have to walk up to them in order to put them back up. Here's a map with the location of all the sticks (snow markers):

First of all, this is what you're looking for:


Hard hats will usually sit on top of a box or barrel, behind a shed or electrical cabinet. Here's a map with the location of all the hard hats:

First of all, this is what you're looking for:


Posters can be seen around as white boards. They'll be on buildings, but the most common location will be electrical cabinets, on the face that can't be seen from the track. In order to unlock them, you'll have to walk up to them and a poster will be put up.


Here's a map with the location of all the posters:

First of all, this is what you're looking for:


Signs are just metal rods sticking from the ground. They'll usually be near crossings or houses, but some are in really illogical areas. In order to unlock them, you'll have to walk up to them and a sign will be placed.


Here's a map with the location of all the signs:

I’ve come across some weird bugs. At some point I had all the hard hats, left the game, came back a few days after, and was missing the last one again. So if this happens, use Camera 8+Shift+Arrow Keys to fly around the map to find (again) the missing collectible.

The safest seems to be exiting to the Main Menu, and after exiting the game.

Here's what the game should be showing you once you find all the collectables:


This is how the map will look like once you've found all collectables (PaintSkills™):


Anyway, thanks for stopping by, and I'll see you in the next guide, as Dovetail decided to include more of these ♥♥♥♥♥♥♥♥♥♥ stupid collectables in GWE.

PS.: Any questions, leave them below, I usually answer in the day or the following day. Spam and inappropriate comments will be deleted.

Special thanks to Rose for proofreading and nickhawk for helping with the last marker.

PS.2: Yes, I used Paint for the maps and stuff. Proud of it, actually.