Here is the Samsung Gear S2 3G SM-R730T PINOUTS diagram for those who wants to solder a usb wire into their watch. This is when your watch download wireless mode is not available and its bricked.
Guide to Connecting a Samsung Gear S2 and S3 Device Using Wi-Fi Here you will learn how to connect a Samsung Gear S2 and S3 watch to a Host computer by your local wifi Wi-Fi Connection or by a wire. You will need to have a computer, a router or access point and your watch as described in this figure 1
By this method you will be able to put your watch into download mode and install firmwares by wires that you will need to solder inside your watch.In case your watch keeps rebooting over and over and then dies, or you can't connect over wifi/bluetooth connection or you had an update and crashed your watch, so here is the method used to fix that problem.
Finally Samsung Gear S3 reactivation lock got unlocked. And there is way to reset reactivation of Samsung Gear Watches. Below is the method used for this purpose. This solution will help to reactivate a locked google account of watch. You need to download a Combination , and Firmware files and some other files used for this method.