Yeah it takes practice. Start by just meditating on a holy symbol of some sort.....Hindu, Hermetic, whatever. When you can hold your concentration for the entire trip you can try more elaborate rituals.
I would never make a Salvia designed ritual as elaborate as a regular ritual. Mine are insanely simplified because of the reaons you mentioned. Salvia has a mind of its own and even holding a sigil in mind through a trip can be a challenge.
Not that it isn't fun and useful to go with the flow on Salvia Divinorum, but there are definitely reasons to stay focused on the original goal you had going in.
xoxo
izabael
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