You need to install/setup saprouter on the target machine and configure the saprouttab with or without SNC. To configure the saprouttab with SNC you need to get the get the new SNC name from SAP.
After installing the saprouter on the new server you need to register the IP with SAP through an OSS message. If you are using SNC then they reply back with a new SNC name which can be used for configuring the saprouttab. After configuring the saprouttab start the saprouter on the target machine and also adapt all SAP systems to use the new saprouter using Tx OSS1.