The BMT experience is anchored on several high-key events, and everything else is a build up towards one of these.
Rifle Presentation
See full article here.
This is a standalone and almost random series of ten combat lessons, where you learn to punch, elbow strike, kick and knee jab.
Live Range
Marksmanship is pretty much a fundamental of being a soldier, so this is obvious. Interesting points include the Individual Marksmanship Trainer, which is the most realistic arcade shooter ever, and the Company Best Shot tournament, where your commanders use their imagination to test you (one of the companies in my batch used a fruit bar at 100m away for the test). There will be a Ninja Van (a civilian operator selling potato chips, chocolate bars, canned drinks etc.) so bring lots of money if you want to make friends.
Be prepared to sleep at 3am on this day, because range procedure eats up a lot of time.
Field Camp
This is generally considered the toughest hurdle that a recruit has to overcome, being the test of all the field craft he or she has learned to date. Full article here.
SITest
For leadership batches, and selected recruits from other ones. This is the more relaxing outfield opportunity, and your first taste of the MATADOR - an anti-tank weapon that you have to carry everywhere, weighing 9kg. Basically, you spend your time in a group going from station to station. You simulate scenarios like crossing a river, bombing a bridge, crossing a gorge, rescuing a prisoner and other interesting ones. My main advice on this point is to learn your stuff well! Knots, explosive circuits will all be used in the course of this activity. Also, be creative and very attentive to how the requirements are phrased, so you don't waste time on things that are not needed.
Example of a station:
Mission is to bring ammo box across the river. Notice that no one said that all your men must get across also, so you can just get one guy to the other side and construct a rail to slide the ammo box to him.
On this note, time is tight on many parts, because they want to test how you respond under pressure. They may tell you that you have half an hour, but five minutes later, they will announce a sudden enemy unit approaching. Always assume that the time they give will be cut short.
Also be prepared for snipers to suddenly engage you, so there might be casevac involved (see Field Camp).
Hand Grenade Live Throw
Don't need to think too much, just follow the instructions here. The explosion is louder than you think, and the ball bearings sometimes can fly all the way to where everyone else is sitting and waiting for their turn (quite alarming). If you throw wrongly, the grenade may fail to detonate and you will have to crouch for half an hour.
Route March
The best advice I can give for this is to realize that, ultimately, you will reach the end. You can feel like crap along the way but it's a confirmed, don't-need-skill event.
Consider buying high quality army socks and anti-abrasion cream if you want an easier time. Also, sing very loudly and for as long as you can, as this is a good distraction (unless you are Apache, Pegasus or Ulysses, and you don't like people to laugh at you).
The Bread and Butter physical component of BMT.