Timisoara can be reached:

by plane:    – directly to Timisoara (strongly recommended);

The English web page of the airport in Timisoara contains useful information about flights and access to/from the airport. The airport is 12km far from downtown (where the conference venue and most hotels are located). A taxi from the airport to downtown should cost around 35 lei (8 euros). Uber is also available in Timisoara. Information for access with public transportation (bus E4) can be found here.

to Budapest, where several low cost airlines fly from western Europe.

There are several companies which provide shuttle service between Budapest airport and Timisoara (5-6 hours); for instance:
Christian Transfers
Timisoara Transfers

to Bucharest, then taking a domestic flight or the train to Timisoara.

by train:      Timisoara is about 9 hours distance from Bucharest, 6 hours from Budapest (Hungary) and 3 hours from Belgrade (Yugoslavia).

The web page of the Romanian Railways is here (click on the link for English in the upper left corner). To look for international train connections all over Europe, a good place is the site of the Austrian Railways. The required destination should be Timisoara Nord.

by car:       If you travel from Western Europe take from Wien to Budapest the freeway M1; then after Budapest M5 all the way to Mako (after Szeged). Exiting the highway look for signs directing towards Timisoara (you will cross the border at Csanad/Cenad and pass afterwards through Sannicolau Mare). Alternately, from Mako you may cross the border at Nagylak/Nadlac towards Arad and then take highway A1 to Timisoara.