In pretty much most tank battles in DH, sound is about 80% of the battle, and the tanker that uses it better than their opponent will most likely win. To get very good sound, consider getting high quality Headphones or something. After that or before, you'll also need to learn the different sound classes each tank will make. For an example, all varients of the M10 tank destoryer and the M18 hellcat will produce the UStankdestroyer sound class (not sure of the exact name), which means that those tank destoryers will produce the same sound. You'll find this pattern quite a lot where multiple tanks share the same sound.

To use sound effectively, you must camp with your tank in an unpredictable spot and listen. When driving you tank, you'll find it very hard to spot other tanks via sound, unless said tank is very close to you. Also, turning off your engine really isn't needed that much, as you'll still hear very clearly with an idle engine. Turning on your engine after you've turned it off makes a very loud noise, and enemy tanks can very clearly hear it even if they're driving their tank at the same time.

When tankers use sound to spot, they're most likely playing defensely, and when they do so, they'll very much have the advantage as they'll most likely have the first shot. To counter this playstyle, you'll have few options to consider. first, you could engage the camping tank from long range, thus minimizing the camping tank's advantges in sound and putting you and the camping tank on an equal level playing field.
The second option would be engaging the camping tank by using infantry mayhem to your advantge. Infantry mayhem really isn't a term in DH, but it's one that i've thought of recently. It basically means all of the sounds and smoke infantry produces. Gun fire from various types of guns including infantry held MG's and such can really impair a camping tank's ability to hear clearly, and especially at close range. Smoke and other distractions from infantry can also assist you on moving up and taking out that camping tank.
Lastly, you could also avoid the camping tank entirely and focus on an objective that'll want that camping tank to come to you. For an example, mowing down infantry, or attacking an HQ will put pressure on that camping tank to come to you and deal with you. From there, you can listen and camp to have the first shot off.

Also, when given the oppertunity, flanking the camping tank is also a good idea.

When positioning your tank, you'll want it to be relatively safe from harm while still being very effective. In an infantry support mannor this means being close, but not too close to the point where tank hunters can easily flank and destory your tank. You'll want to be close to the point where you'll easily spot the enemy infantry while still being far away. Joining squads can also help in your positioning, as you'll clearly see when your infantry squad members die, and where they need tank support and provide it. It's also recommended, that when you're providing infantry support, to pause for a minute, and listen for enemy tanks trying to take you out. If you do hear an enemy tank coming to you, try to reposition and further listen for the enemy tank.

When trying to take out other tanks, you must choose a spot that's both unpredictable, hard to spot, and gives you a lot of view. When trying to flank tanks, it's mostly fail proof to do so when the tank you're trying to flank is providing infantry support to its enemy infantry. Whilst they're firing off their coaxial machine guns and their main cannon, it'll make their tank very easy to spot sound wise, while at the same time also making it harder for them to spot enemy tanks sound wise for them. They'll also have HE loaded, so if they manage to get the first shot off, it'll be mostly harmless.

Foilage is generally a high risk, high reward map characteristic tankers can use. Sometimes, it could make their tank harder to spot, however, it'll also restrict most of their view at the same time, so it's paramont to be thoughtful when moving into a bush plant, as it could pretty much restrict most of view, while at the same time, make your tank not drastically harder to spot.

For an example, you'll want to concel your tank in foilage that'll easily compare to the tank's colour scheme, the terrain must also be comparable to the tank, and the foilage that you're hiding your tank in must not be in the way of the tank's gunsights.

This is the perfect hiding spot that meets all of the criteria:



From afar, this is what the enemy tanker will have to contrast amongst the landscape in order to find the tank without binoculers:

-Map knowledge is important for tankers, so it would be better to go infantry first so you can learn the general layout of said map.

-Angling your armor can actually be useless most of the time, however, it's very useful for a few amount of tanks depending upon their situation.

-After destroying a tank, or causing great mayhem to an enemy team, it's smart to reposition your tank so you won't get easily destroyed.

-Angling your screen on maps with lots of fog can actually increase your viewing distance, for an example, making your character view the far left side of the map can increase the amount of stuff you can see on the far right side of the map (this is caused by some weird bug in RO's engine).