I"m a bit lazy to write all the steps necessary to get decals on straight where they belong. It's a lot of detailed writing and editing to make sure the entire process is clearly understood. Call me, I'd rather tell you over the phone. PM or email me if you don't have my #. The process starts with the right tools. I use a section of 3/4" aluminum angle I bought at the hardware store. This is a guide when placed along a tube for making sure a decal is straight without climbing up or descending. The other most valuable tool to me is a half section of tube with a squared end. This is for getting decals straight across from each other and/or not being twisted. For example checking that a seat or head tube decal is not crooked. Since I am a frame builder/painter I have just the right size tubes in both wall thickness (0.058" is best) and diameters. For example if your seat tube is 1 1/8" in ø than a 1 1/4" OD tube with a wall thickness of 0.058" split longways in half will fit perfectly over your seat tube. Before I cut the tube in half and file off any sharp edges, I square the end of a whole tube on my belt sander or use my lathe. Tubing with thinner walls can work okay too.
The 3rd and 4th tool required is masking tape and a pencil. The angle and half tube can help you place your masking tape in just exactly the right position before marking on it to show where the decals need to be placed next to it. You will also probably need to make tiny marks on your decals (before taking off the backing paper) to indicate centers or some other reference in relation to the marks you put on your masking tape now on your frame. Once you have those tools in your position, call me and I'll give you much more detailed instructions. Or maybe someone will post that has more patience writing than me
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