The Oracle knows all, The Oracle sees all.
Firstly, if you first thought is ‘It is impossible to pass your CCNA in 4 weeks then please read no further, you can’t be helped. If your first thought is ‘How can I pass my CCNA in 4 weeks’? then you are in the right place.
First things first. Remove all distractions such as TV, friends, cinema and a social life (for a short while only of course). You will need a huge amount of focus and effort and if you are out of the study habit then this step is even more important for you.
If you are a novice then you will want to start out at the very beginning. I have seen quite a few people pass with only 4 weeks but they were very determined to pass and had a huge focus. Three of them were going to be sacked by the end of the month if they didn’t pass and this sort of thing tends to aid the concentration somewhat!
Plan to study for 2-3 hours per day. Do whatever you have to to make the extra time including getting to work 2 hours early and finding a quite room and taking your lunch somewhere quite. Take any holiday you can or days owing.
Read the Underground CCNA Cram Guide for 20 mins per day and listen to the audio in your car or whilst travelling. Do 30-45 mins hands on lab practise per day using the hands on labs section. Read up on one area per day such as OSPF or Access Lists. Next ensure you can answer any subnetting or design question within about 20 seconds. You can do this with continual practise of 20 minutes per day.
The final step is to do a practise exam every single day. There is nothing like the pressure of having to answer a question with a time limit to test your knowledge.
Use your instinct to judge what your weak areas are and work on them until they are your strong points. When you take the exam you want to be more than ready, you want to be passing in the high 900s and not just scraping by.