Untar the package verilog_systemverilog.tar.gz
Copy verilog_systemverilog/ftdetect/verilog_systemverilog.vim to your $HOME/.vim/ftdetect directory.
Copy verilog_systemverilog/syntax/verilog_systemverilog.vim to your $HOME/.vim/syntax directory.
Copy verilog_systemverilog/indent/* to your $HOME/.vim/indent directory.