I guess speaking verbally is the way to go?
That's one way to go.
How do we resist the devil?
By all means. E.g.,
and do not give the devil a foothold.
Therefore take up the full armor of God, so that when the day of evil comes, you will be able to stand your ground, and having done everything, to stand.
1 Peter 5:
Be sober-minded and alert. Your adversary the devil prowls around like a roaring lion, seeking someone to devour.
7 Therefore submit to God. Resist the devil and he will flee from you.
OP: James makes it seem like we resist him once & then the devil will flee.
Verb - Aorist Imperative Active - 2nd Person Plural
Strong's 436: To set against; I withstand, resist, oppose. From anti and histemi; to stand against, i.e. Oppose.
This is not aorist indicative but aorist imperative. This is a case of non-past aorist.
Resist the devil at once and finish your job of resisting. Then the devil will certainly flee. The whole job is considered as a single discreet event.
When the devil comes back, resist again.
It happened to Jesus in Luke 4:
When the devil had finished all this tempting, he left him until an opportune time.