Get the Whitepaper called Reversing Basics – A Practical Approach. It discusses reverse engineering a simple crackme using IDA Pro.
You can download it from the following link: https://packetstormsecurity.com/files/download/99375/reversing-basics.pdf
Source: https://packetstormsecurity.com/files/99375/Reversing-Basics-A-Practical-Approach.html