A Spectrum Summon (スペクトラム召喚 (formatted as Ｓｐ召喚 exclusively in card text) Supekutoramu Shoukan) is the method of Summoning a Spectrum Monster. To Spectrum Summon a Spectrum Monster, you must first have a complete Spectrum Wheel, which is done by adding Spectrum Pieces to it via card effects. When your Spectrum Wheel is complete, rather than use Material Monsters, you must then pay Life Points to perform the Spectrum Summon. The Life Points you pay must be equal to the Wavelength of the Spectrum Monster you are trying to Spectrum Summon multiplied by a certain multiple of 100, primarily between 300 and 700, the multiple being on the card (ex. 500x LP + Complete Spectrum Wheel). Once you've done this, you can Spectrum Summon that Spectrum Monster. Sometimes, you might have to remove Spectrum Pieces from the Spectrum Wheel in addition to paying Life Points to Spectrum Summon a monster.
So long as your Spectrum Wheel is complete and you have enough Life Points, there is no limit to how many times you can Spectrum Summon in one turn.
The basic Summon chant for a Spectrum Summon is: "Radiant light of the rainbow, combine your seven colors and create a new power! (虹の眩しい光は、あなたの7色を組み合わせて、新しい力を作成！ Niji no mabushīkō wa, anata no nanairo o kumiawasete, atarashī chikara o sakusei!)"