You can get step by step information for Creating cubes in Ax 2012 .   http://dynamicsaxforum.blogspot.com/2013/07/creating-cubes-ax-2012.html#!/2013/07/creating-cubes-ax-2012.html   Customizing cubes   http://dynamicsaxforum.blogspot.com/2013/06/customize-cubes-ax-2012.html#!/2013/06/customize-cubes-ax-2012.html  
Technical Tutorials x++,tips on issues or troubleshooting On Ax ERP ,Microsoft Dynamics 365,Ax 2012,Microsoft , U.S.,Business Software solution.