Here's an overview of the map including call-outs that are helpful to know.
We're back! This time we'll go over how to attack on Train. At first this might seem a little tricky but as long as you use smokes before you attack you should be able to pick up a few rounds. There are a few reasons why smokes are so important on Train. The first being the long distances and how easy it is for an AWPer to kill you as you initiate the push. The second is that it helps you get the bomb planted. Unless the CTs climb trains or go through a smoke, they can't really know how many terrorists are there.
One thing to keep in mind is how separate the bomb sites are, and that you need to control ladder room if you want to be able to rotate effectively. Most of the time these rotations will be quite obvious and the counter-terrorists will be able to get to their next stop much earlier than you’re comfortable with. Chances are that you will find more success if you execute a pre-planned strategy towards one site after you've gathered information and maybe even picked up a kill.
Smokes on A
Let's dive into the fine art of smoking bombsite A. There are some really useful smokes on the outer trainyard. Because I'm a good guy and I care about your browser's well-being I'll include two smokes per gif (with a hard g).
The first smoke is going to cover the area between connector and bomb train to make it easier for a terrorist to attack from ladder room without getting killed. The second one will smoke between the brown train and the bomb train to make the last part of your journey with the bomb a little more convenient.
You will also want to smoke on either side of the blue train. Here's how to do just that:
If you use all of these smokes you are almost guaranteed to get the bomb down, but there are problems. The defenders will be able to attempt a retake with five players still alive and you won't have any smokes left for the choke points after the plant. Of all these smokes, the one to the left of the blue train is the least important in the sense that it doesn't help you transport the bomb to site. The smoke does however make it less attractive for the CTs to attempt a backstab. If you don't want to use that smoke you can peek that lane with an AWP instead. Or you can leave a gap somewhere else, as long as you have a plan and are ready to challenge your opponents.
After you have planted the bomb it's very important to communicate. Make sure you have ladder room covered. I don't know how many times my team has been sprayed down from there just because we failed to communicate. Especially if the guy who's supposed to take care of ladder died during the push. Make sure you take post plant positions that will make it easy for you to peek towards the bomb.
On the next page: attacking bombsite B.