Although this is not a reccomendable way to make something bolder,
you may try this:

+ Type something in your Photoshop
+ Select the text layer
+ From the top menu, go to > Layer > Layer Style > Stroke...
+ Now you can decide the stroke thickness and also can change the color of the stroke as same as your text.

I hope this will help.

If you're type is already rasterized it's easy. There are two methods.

Method 1. Make a loose selection with the lasso tool and then (holding option or alt) deselect the white surrounding the letters. Make sure your tolerance is set low for the magic wand. Go Edit/Stroke. Select 1 pixel (Black) on Outside. This will add just a tiny bit of weight. If not enough undo and try more.

Method 2. Select around letters again with the lasso tool. Go Filter/Other/Minimum. A window will pop up with a preview. Again, try 1 first and see if it's enough.

The Minimum command tends to be a little heavier in adding weight, but is usually smooth. I think if your type remains vector you might also be able to convert it to a path and stroke that path in the paths menu. I haven't tried that so can't help you there.

Stephen

If at all possible I'd add the stroke/make outline stroke thicker in Illustrator or any other vector based application. If you must do it in Photoshop, follow the suggestions above.

These are all poor substitutes for a real bold of course. But I expect you knew that.

Thanks a lot for all the answer, I `m trying all the methods. This was really help full, thanks to all

Make sure you keep a record of what you did. Especially if you are doing it for a client. A year from now when they want to change a word or add to the line, you will be glad you made that record.