Ljubljana is very well connected by public transport (bus, train) with other places in Slovenia.
You can reach Mini Teater from the main bus and train station by taking a bus operated by Ljubljanski potniški promet (LPP). Here are some options:
Bus Lines
Line 2: Takes you to Križanke station, which is close to Mini Teater.
Line 3: Takes you to Gornji trg station, from there it's a short walk to Mini Teater.
Line 11: Takes you to Kongresni trg station, from there it's about a 10-minute walk to Mini Teater.