Getting started in Mekanism can be difficult, but that is far outweighed by the benefits of having machines that can let you fly, literally. The first thing to do is to creat a Metallurgic Infuser. That is crafted with 2 redstone, 2 furnaces, 4 iron and an osmium ingot. This lets you create steel, which is a critical component for most other machines, and control circuits which are essential for every Mekanism machine. The next machine to make should probably be the Enrichment Chamber, which lets you double ores and help with the efficiency of your Metallurgic Infuser.