A question about an article by Birman, Series

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I've asked this question on mathoverflow, but I thought it may be helpful to restate here since I guess it might be a not so hard question to solve.

The link

Birman and Series in their article GEODESICS WITH BOUNDED INTERSECTION NUMBER ON SURFACES ARE SPARSELY DISTRIBUTED proved that the set of points on a hyperbolic surface (possibly with boundary) belonging to complete geodesics with at most $k$ self intersections are nowhere dense and of Hausdorff dimension $1$.

In section two of this article, they introduce non-exceptional geodesics relative to a fundamental region $R$, which are the complete geodesics that don't pass through the vertices of the fundamental region $R$ or don't have self intersections on the vertices. They claim that we can take $3$ fundamental regions so that any simple complete geodesic is non-exceptional relative to at least one of them.

I was trying to justify this part for myself, and I wasn't successful. Could it be possible for someone to help me prove this part.