Lifts must be done in that order. Once you warm up, you will have only three attempts to set a 1RM in each lift.
Strategy on the CFT from Mark Rippetoe (inventor of the CFT): The first attempt would be a weight you know you can do for a heavy set of three. The second attempt would be a weight you know without any doubt that you could do for a single, having just done the first attempt. And the third attempt is the weight you want to do, based on your performance on the previous two attempts. If you have made a mistake setting your first attempt, the next two will need to be adjusted, but you should know what you can triple, and this will always be a safe first attempt. And since you know this weight, you know what weights to use to warm up for it: youâ€™ll use the lightest weight that you normally start with for your first warm-up when you train, and 90% of the first attempt for the last warm-up, with either three or four relatively even increments in between these two.
Read more about the CFT here.