If it's your first time, it might help to get an assistant. You'll need to depress one side of the spring bar in while the bracelet is being slightly pulled away from the case. Depress the other side and it'll slide off. It is possible to do it yourself once you get the hang of it. And it is preferred to push the endlink towards the bottom side (pushing it in from the front) to minimize the scratches on the inside of the lugs as opposed to downwards from the case.
Either that or find a pair of that tweezer-style spring bar tool.
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