After leaving the hotel. You should move down from the right side. After an average of 10 minutes walking distance, you will reach the train station. Station name is DEMİRTAŞPAŞA.  You will find the station in the picture you see below and from this station.

With this link you will reach Google maps  Click

Here you will get on the train No. 1 and you to get down at the last stop at the EMEK station.

After your train journey is finished, you can go directly to Mudanya by small yellow buses.

After landing at the train station, you will see these buses across the road.

There are 2 buses you can use here. The first auto is M1. And the other is 1/GY bus.

It goes to the ferry station.

    M1  Mudanya Ferry Station BUDO ferry.

     1/GY bus goes to the IDO Station, which is a Güzelyalı ferry station.

   (Ferry Station  İDO)  for  Yenikapı-Kabataş-Kadıköy-Armutlu

    You can find detailed information about these from this link.

BUDO - Bursa Deniz Otobüsleri (burulas.com EN.

İstanbul Deniz Otobüsleri - Online Bilet Al | EN.

You can also reach there by taxi.  If you have a lot of luggage, this will be more comfortable. Since taxi fares vary, please get information from the taxi driver. You have the opportunity to bargain.