In short: 1) remove the screws 2) take the screwdriver and put it into the notch of the dynamic !!! The lid is connected to the main part of the watch with the cable: do not break the cable while opening !!! 3) carefully increasing the power, remove the back lid 4) near the battery you will find a couple of screws. Choose the closest one. It holds smaller metallic holder. 5) remove the screw 6) remove the metallic holder, lifting up with the tweezers (more convenient to hold it for the part, which is opposite to the removed screw) 7) disconnect the battery with the tweezers 8) battery is glued to the lid. However, it is quite easy to remove the battery, lifting up with the plastic pick. 9) replace the battery and repeat all the procedures in the opposite direction