Big congratulations on your first work! A bit of advice: If you're making art with words, spend time on the design. For neon it's all about continuous lines, think about how the words flow together. No matter how many tubes you got, your art should look like one solid piece. …

Neon sign designer here. It seems like this is less an issue of letter spacing and more a problem with design layout, especially if the letters weren't immediately identifiable. Aside from the uneven space between the words, capitalization could also have been used strategically to make it more readable. They …