Here is a useful tool. You can place a bitmap image to trace. Go to View > Background Bitmap > Place
placing a bitmap
I usually start at the origin, and the bitmap shows up on the top view. I don't worry about making it to a scale because I will scale my drawing after it is finished and I am ready to remove the bitmap. So here is a wine bottle that I will trace and revolve so that I might have some stuff on my shelves eventually. I will begin with a vertical line about the height of the bottle, and then approximate the curvature up from there. It is kinda hard to see, and it would work better if I'd taken a straighter picture, but you get the drift. I'll add a little line at the top for the cap, join the lines and then remove the bitmap. View > Background Bitmap > Remove Then I select everything and scale it to the correct height. My bottle in real life is 1 foot tall, so my first point is the top curve at the end, and my reference point is straight down and lined up with the bottom of the curve. Then I type in 12" and it is the right scale.
I won't put a bottom on my bottle because nobody is going to see it. So here is my profile which I will revolve around the end of the line I last drew. Surface > Revolve Select the curve and press enter. The start of the revolve axis here is the end of my (cap) curve. Then it asks for the end of the revolve axis, which I want to be straight down, and I click past the bottom of the curve while holding shift or in ortho mode to make sure my revolve axis is completely vertical. The start angle of 0 is fine so I hit enter. And I want it to revolve all the way around so the angle of 360 is correct and I hit enter again. (if I click on the screen anywhere the revolution angle will stop wherever I click)
Now I have a simple bottle I can put on a shelf, but its placement is a little off. I want it above the origin point so that when I insert it on my shelf in the main file it will not be falling halfway through! And I also want it centered on the origin in the x direction so it is easier to line up. I think I'll draw a reference line to help. Plus, I have Snap on so it will snap to the origin. This is fine if I'm inserting the bottle on its side on a flat shelf.
What if I have scissor shelves like at so many wineries? Here is an example of that situation. I just drew a line flat and rotated it up 45 degrees, then I mirrored that so it would be symmetrical. This represents the top surface of the angled shelves I might have in the other file. (I use SetPT in the Y direction if they get a little wacky) Then I repeat from the center of the cap to the edge of the bottle at 45 degrees. Now I will move the bottle up. Then I delete construction lines, and when I insert the block it will snap to the bottom of the V shape in my diagonal shelves properly (assuming my shelves are all at a 45 degree angle).