In order to tell you the most efficient way, we will need to know whether you are using a mouse or a track-pad, and their sizes and position relative to your keyboard; we will also need to know your keyboard layout, and will need to know your operating system and to know whether there are certain key combinations that you need to preserve for use with other programs or facilities. We will also need to know your MATLAB version. Oh, and your arm length, your fore-arm length, and whether you have standard range and efficient of motions or are restricted in your motion. Also, we need to know the extent to which Repetitive Strain Injury movements need to be avoided. We will need to know these things in order to be able to calculate the minimum-energy patterns for your interaction with MATLAB / Simulink.
We will, for simplicity, assume that you are able to remember 64 things simultaneously, and that you are able to plan 32 steps ahead, instantly. We will also assume that you never make a mistake in entering information, and that you never need to debug what you have created, as making mistakes or having to debug is not efficient.