How do i change the battery on a Jacque Leman 1215 watch?

Casebacks can be attached in several ways. The most common is a snap-on type. The back will be smooth and if you look closely around the edge you should see a small slot somewhere along the edge where you can insert the edge of a caseback removal knife - it looks like a small oyster shucking knife - to pry the case open. The caseback me be very difficult to snap back on and require the use of a caseback plier or pressing tool. If the caseback is held in place by screws, you can carefully unscrew them using a good quality jeweler's screwdriver. the real cheap mini-divers will bend and scratch the watch. Another common method is a screwdown caseback. You will see indentaitions on the edge of the case back to recieve a caseback wrench to unscrew it. If your watch is water resistant, don't forget to replace the gasket as they are only good once. Most watch shops will replace the battery while you wait for about $8 so that may be your best bet.

Many watches use special caseback remover wrenches. You may need to go to a jewelry store that does watch battery changes to get it done.

You need either a caseback knife or caseback wrench depending on whether it's a screwdown or snap-on back. If it's a snap-on, you'll also need a caseback presser to put it back on. Using the wrong tools can easily cause damage to your watch. If the watch is "water-resistant" be sure to replace the gasket as well or it will leak - you cannot reuse the gasket. You best bet to do this without having to buy tools, find the correct battery and gasket and risking scratching the watch is to let a watch shop or jeweler do it. Most places will charge about $8 to replace the battery and gasket. Sears sometimes charges only $4 so either way it's worth it. Even though I have the tools myself I usually bring my watches in and have it done since I'd have to go out and buy the battery & gasket anyway.

You will either find a very small lip that accepts a prying tool or you may see some indentations for a caseback wrench to unscrew it. Any jeweler or watch shop (including Sears) will change the battery for less than $8 and ensure that no damage is done and that the gasket that provides water resistance is replaced (insist that they do!). DO NOT reuse the gasket even if it looks undamaged. It will not keep water out if it is reused.

Identify first if it is a "screw on back" or a "pop off" back. Screw on backs have multiple indentions on the caseback where a special tool fits in the grooves to twist it on and off. If it is a screw type back then you will either need to buy a pricey caseback wrench or take it to a jewelry store that changes watch batteries.
A pop off back will have a smooth caseback with no indentions on it.
Most of these are "pop off" backs. to pop the back off get a very sharp blade and apply pressure at about a 30degree angle between the case and the caseback on the underside of your watch. From there you should be able to pry it and it should pop right off. Another way is to put a razorblade between the case and caseback, tap the blade with a small hammer (lightly!) and then pry the back off.

ooh, ESQ by Movado. These case backs are often pressure fit, just like Movado, and are notoriously difficult to reinstall. It sounds like it is going to take a watch press to install your caseback. This is an expensive tool which any jeweler that changes batteries will have. There is no real safe way to this without a press.
Now, I have just supposed that this is a pop off; if it is a screw on back then it would have had to have been unscrewed to get it off. If it is a screw-back then you will likely need to get a caseback wrench to tighten it down enough.

There is a reason why Bulova watches cost so much when you need to replace the battery....it's DIFFICULT! You can try the following, but I would HIGHLY recommend having a jeweler replace it for you. At one time Walmart did it for next to nothing, but I don't know if they do Bulova watches at this time, but it costs nothing to call them.
Try this AT YOUR OWN RISK:
The best choice for removing a threaded caseback is to use a "caseback removal tool", which consists of two or three adjustable "pins" attached to a handle (most WalMarts sell a two-pin tool in their jewelry department, and you can purchase a better three-pin tool from several vendors on eBay). To use it, start by placing the watch face-down on a padded surface (to avoid scratching the crystal). Adjust the pins so that they very snugly fit into the notches cut into the caseback; if you don't, the pins can jump out when you try to use it and scratch the watch. Place the tool over the caseback and engage the pins into the slots; then, holding the watch steady with one hand and the tool in the other, give the tool a counterclockwise turn to loosen the back (it may take a lot of force to do this, especially if this is the first time the battery is being replaced). Once the caseback is loosened (usually about 1/4 to 1/2 turn), remove the tool and finish unscrewing the back by hand to avoid scratching the watch. Be careful as you remove it as some watches use a very thin O-ring on the back to make a watertight seal.
Afer replacing the battery and ensuring the watch is running properly again, carefully inspect the surface of the case and the threading on the caseback and remove any dust or grimy deposits with a soft cloth. Then, place the caseback onto the case, being careful to align the O-ring or other seals, as well as the caseback threads (tip: to ensure the threads are lined up, place the back on the watch and turn it counterclockwise about 1/2 turn or until you feel the ends of the threads "fall" into place). Screw the caseback down as far as possible by hand, then use the removal tool to tighten it the rest of the way.

There are 2 ways that Fossil closes the caseback on their watches.  It is either a 'pop-off' caseback that you will need to pry off.  Get something very small and thin, such as a small flathead screwdriver.  There is usually a small groove somewhere around the edge of the caseback where you can insert the blade.  The other type screws off.  You will need to unscrew the caseback.  You can determine if it screws off by looking for 6 notches around the outside edge of the caseback.  You will use these notches to insert a tool to rotate the caseback off.  Without a specialized tool called a watch-wrench, I suggest bringing it to a store such as Precision Time or Tourneau.

You need a watchmakers knife or caseback opening tool to open your watch.
1)If your watch has screwdown back, there should be grooves in caseback where you have to put in opener and unscrew that caseback.
2)If your watch has a 'clip-on' caseback, you have to carefuly examine the caseback and find the groove between caseback and watch case (it is called 'the lip'). This is the right point where to insert the blade of wtchmakers knife and open it using pressure and lever action.
3)The safest, but dearest way is to visit your nearest watch repair shop and ask for battery replacement. You may ask the watchmaker to show you how to do that, so, in future you can do that yourself.
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