I'll let you know which way to go when we get closer.
1) I'll give you directions once we get closer.
近くに行ったら道案内します。
道を案内する は give directions です。
近くに行ったら は once we get closer, when we're close, when we're closer などといえます。
2) I'll let you know which way to go when we get closer.
近くに行ったら道案内します。
I'll let you know which way to go は直訳すると どっちへ行くか教えます で、道を案内しますと同じ意味です。
Once we get closer, I'll give you more specific directions.
This easily lets your taxi driver know that you know where to go and that when it is necessary that you will give them directions. I hope that this helps :)
2) I'll give you directions once we're almost there.
道案内します: I'll give your directions / I'll show you the way.
1) I'll show you the way when we get closer.
"近くに行ったら道案内します" という意味です.
2) I'll give you directions once we're almost there.
"もうすぐ到着の時は道案内します" という意味です.
I'll tell you where to drop me off when we get closer to the destination.
I'll let you know where I want to be dropped off at when we get closer to the destination.
I'll tell you where to drop me off when we get closer to the destination. - This sentence can be used to express to the driver that you will inform him/her where you want to get out of the taxi once reaching the destination. The phrase "Drop me off" means "deliver me" or "let me out", this phrase is commonly used inside of vehicles when you are a passenger in the vehicle requesting where you would like to be taken.
Example: Can you "drop me off" at the mall? = Can you let me out of the mall? = Can you deliver me to the mall? = Can you take me to the mall?
You can "drop me off" here = You can let me out here
I'll let you know where I want to be dropped off at when we get closer to the destination. - This sentence can be used to express to the driver that you will inform him/her where you want to get out of the taxi upon reaching the destination.
I'll tell you where to drop me off when we get closer to the destination.（目的地近くになったら、どこで降ろしてほしいか言います）
この文は、「目的地に着いたら、どこで降りるか教えます」と運転手に伝えたいときに使うことができます。
"Drop me off" は "Deliver me"（届ける）や "Let me out"（降ろす）という意味です。このフレーズは、運転手にどこで降ろしてもらいたいか伝えるときによく使われます。
例：
Can you "drop me off" at the mall? = Can you let me out of the mall? = Can you deliver me to the mall? = Can you take me to the mall?
（ショッピングモールで降ろしてもらえますか）
You can "drop me off" here = You can let me out here
（ここで降ろしてください）
~~~~~~~~~
I'll let you know where I want to be dropped off at when we get closer to the destination.（目的地近くになったら、どこで降ろしてほしいか言います）
この文は、「目的地に着いたら、どこで降りるか教えます」と運転手に伝えたいときに使うことができます。
Once we are closer I will let you know where to stop.
I'll direct you as we get closer to the destination.
When trying to tell a taxi driver that you will give him/her directions as you get closer to the stop, one can say something like "Once we are closer to the destination I will give you directions as to where to stop." or something shorter like "as we get closer I will give you directions.".
「目的地付近になったら、道案内します」とタクシーの運転手に伝えたいなら、次のように言えます。
"Once we are closer to the destination I will give you directions as to where to stop."（目的地付近になったら、道案内します）
あるいは、よりシンプルに、
"As we get closer I will give you directions."（目的地付近になったら、道案内します）
と言うこともできます。
If you are arriving at a place then when you are not far away you are said to be 'close' or 'near' the place you want to go
To tell someone how to get somewhere is referred to as giving them 'directions' or 'showing them the way'
I'll let you know exactly where it is when we get nearer
I'll show you where it is when we are in the area
When you are riding in a taxi, and get closer to the destination, you would like to know how to say you will give the driver directions for where to let you off. Either of the above two suggestions is fine for that situation.
I will give you directions closer to my destination!
When taking a taxi, we normally tell the driver to which area he has to take us, we don't need to direct him from the starting point to the finishing point/destination. So you can tell the driver:
"I will give you directions closer to my destination!"
"I will tell you where to drop me off the closer we get!"
タクシーに乗るときには普通運転手にまずどの辺りに行って欲しいのか伝えます、出発地点から目的地まで道案内する必要はありません。
次のように運転手に伝えることができます。
"I will give you directions closer to my destination!"
"I will tell you where to drop me off the closer we get!"
（目的地に近くなったら道案内します）
アイルランド 
アメリカ合衆国 
モロッコ 
イギリス 
南アフリカ 
