If you use a BW/4HANA instance, you have to use the BW Modeling Tools (BWMT) to build your data model. You could only build Advanced DataStore-Objects (ADSO). If you create a new ADSO, you have to select a BW-Project and an InfoArea. After that you have to define a technical name and a description. You could also use a template to build your ADSO.
On the general view of the ADSO you can choose a model template and define the technical settings of it.
Under Details you can add your InfoObjects, own fields, define keys and group your objects to logical groups. Really cool is the feature of own fields. You do not have to create a lot of InfoObjects anymore.
After you have add your InfoObjects you can define under settings the partitions and indizes of your object.
As you can see it is very easy to build an Advanced DataStore-Object with the BW Modeling Tools. After you have done all your settings, you have to activate it.