Unless you have a ridiculously huge show, it is usually pretty easy to keep your
spike marks within the tape colors. Also there are quite a few colors of
spike tape, I know that we have 10+ colors. We usually
spike everything in a given scene or setup the same color. There is no way that a chair would fit on a table's spikes or that someone would confuse the spikes for the giant piece of scenery upstage with the sofa
downstage. This is also why you have rehearsals, so that the people moving the scenery and
props know where it is actually going.
Sometimes we do make some kind of notation on the spikes themselves (in
sharpie), but it has to be very simple and easy to read without bending over and squinting at it. This might be a scene number or something to that
effect.
You also have to consider that you can't really use bright green
spike tape on dark colored
stage. You don't want your
stage to look like an airport. In general you really should be picking colors that mostly blend in with the floor treatment but show up enough to place the scenery. Sure, nothing blends if your
stage is black, but that is another story. I really hate going to shows where I could figure out where the scenery is supposed to go from half-way back in the
house due to the obscene colors of
spike marks.
Many times at our
theatre the
spike marks go down on
stage before the painters finish the floor treatment. If they are about to paint something really dark they will
cover the spikes before painting, but many times the final
glaze step and sealer will just go on right over the spikes. This dulls them down and makes them blend more, which the scenic designers usually appreciate.
Consider also that you need only
spike the upstage side of anything that needs spikes! This will limit the number of spikes you place and it will usually mask the ones that are in use. You don't need to
mark all four legs of a chair or all four corners of a
platform. It only takes three points to get any of those things aligned and one of those points never moves, it is the
stage! So, don't use more spikes than you need. If you have a piece of scenery that moves in a
track, you only need one
spike where the operator can see it!
Think about how and where you
spike, be logical about it. And don't use packing tape to reinforce them, that is just as bad if not worse than the spikes themselves. There is a great vinyl tape that works much better. If you have a planked
deck or if your spikes span gaps, slit them with a knife in the gap and they won't peel up as easily! Remember, don't use obscene colors that stand out for them
deck unless you have not other choice.
boo! I am not a fan of using packing tape on my 
