Creating a +1 spellcasting focus

I’m trying to create a magical item that increases spell attack bonus and spell save DC by 1. What do I enter into the homebrew item creator? Fixed value +1 or something else?

Modifier: Bonus->Subtype: Spell Attacks->Fixed Value: 1

Modifier: Bonus->Subtype: Spell Save DC->Fixed Value: 1

I'm having trouble with an item, i have made it so as shown by IamSposta but it still shows a +11 instead of a +12. it is a plus 1 magic item.

Quote from Crash212 >>

I'm having trouble with an item, i have made it so as shown by IamSposta but it still shows a +11 instead of a +12. it is a plus 1 magic item.

•  Did you re-save the whole magic item after you added the Modifier?
• Are either the magic item as a whole, or that specific Modifier earmarked to require attunement? If so, did you attune your character to it?