Is it a SaveGame hack or a Cydia Substrate hack ?
SaveGame hacks:
Open iTools
Go to jailbroken Filesystem
Browse to /var/mobile/Containers/Data/Application/Appname //Where Appname is the game you want to place the files in.
Place the files from your computer in the according folder
Cydia Substrate hacks:
Using iFile Download the .deb file Put it on your iDevice using a file explorer (iFunbox, iExplorer, WinSCP, etc.) Open iFile Go to the directory you saved the .deb file Click on it and hit "install" Without using iFile Download the .deb file Open a file explorer (iFunbox, iExplorer, WinSCP, etc.) Drag the file and drop it it /var/root/Media/Cydia/AutoInstall Reboot