Getting to the venue using public transport (15 minute ticket should be enough for the first 3 routes, but won't give you any safety margin for traffic jams):
Going from Bratislava airport: take the bus 61 or 96, get off at the bus stop Trnavská
Going from Bratislava main train station: take the bus 61, get off at the bus stop Trnavská
Going from Bratislava bus station: take the bus 50 or 205 (trolley-bus), get off at the stop Trnavská.
Going from the traffic hub Most SNP (AKA Nový most): take the bus 50 (cross the street, the stop is next to the river), get off at the stop Trnavská. 23 minutes, you need 1 hour ticket.
From Vienna airport (the bus stop no. 4 near the arrival hall exit):
Take:
either the Eurolines/Slovaklines bus (schedule), coming to the Bratislava bus station “AS Mlynské nivy”. Then follow the instructions from the bus station.
or the Blaguss (schedule), coming to the traffic hub Most SNP. Then follow the instructions from the Most SNP.