Step 1
First make a general outline of the shape of the bottle using the pen tool. Fill it with any color.
Step 2
Next make a new layer and draw an outline of where the cap should be. I also made an outline of the cap's base(the green part).
Step 3
Now make another layer and create an outline at the top. This is the end of your bottle.
Step 4
We're going to give our bottle some real colors now. Double click the main outline(in my picture it's the yellow one) to get to its layer style and apply a gradient overlay. Change the black gradient color to #eaeaea and set the Style to diamond. Apply a 1px #b1b1b1 stroke as well.
Step 5
Do the same for the cap, and the top outlines. This time change the gradient overlay style to linear on all of these. The cap base should have a color overlay of #ffffff instead.
Step 6
We're going to create a label for it now. Make a new layer and use your pen tool to make an outline of half the bottle. Fill it with any color. Five it a reflected gradient overlay. I set my gradient colors to a light blue to a dark blue(from left to right on the gradient). I also changed the angle to 0 degrees. Just make sure the lighter color is between the 2 darker colors. Look at the picture for reference.
Step 7
Go back to your main outline and give it a bevel and emboss. Depth to 211, size to 13, soften to 5, angle to -90, and shadow mode color to the color of the 1px stroke we set before.
Step 8
Goto the label layer and apply the same bevel and emboss. This time change the color of the shadow mode to a color that matches your label. Do the same for the cap, but uncheck Global Light on the bevel and emboss. Change the angle to 90 degrees and size to 2.
Step 9
Now make a new layer and put some text on your bottle. I used Tahoma for the font and #000000 for the black and #ffffff for the white text. Put the name and some information about your product on the bottle. Finally add anything you think will make the bottle look better. I added a white wavy cover over the label.
Final Result:













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