Hi Universe,
I completely understand your situation because I struggled with that, too, when I ran into it during my first readings. If you're using a significator card as the focus card (the central, middle card of the Line), then you must "charge" that specific card as the significator by visualizing the situation you're asking about and "superimposing" it onto that specific card in your mind, like pasting a photo onto Microsoft Word on the internet, but in this case it's onto your chosen card. Then you shuffle up, making sure to focus WELL on your question throughout shuffling. Cut, shuffle, cut again, etc., until you feel you and the cards are ready.
When I use a significator card in my Line readings, I prefer to turn the deck face-up and look through the cards to find my significator card, and the cards on the left side (YOUR left side – these are the cards read on the left, yes) and the cards on the right (YOUR right side – these are the cards read on the right, yes). Then just lay them down how they came out and read them.
However, in the case that your significator card is either the very first or the very last card of the deck when you turn it face-up, then do still take the significator card and whatever cards landed before/after it and interpret those in the way they are interpreted: cards on the left as what has already happened or what is currently passing, and cards on the right as what is coming in the near future or what has yet to pass. I was taught to reshuffle with the same question but revised a little, so you're not asking the exact same question verbatim, and to see if this changes the placement of the cards any. If the significator card ends up still being either the very first or very last card, then it is clear that the answer cannot truly be gleaned right now. Ask again at a later date.
From Mrs. Rana George's
AMAZING book The Essential Lenormand, which if you're not already reading please go out and pick up your copy – it's the BEST Lenormand book on the market and I never refer back to any other Lenormand book than this one –
"In case the card chosen as the significator or focus came up as the first card, I still pull three cards after it and read them. If I am not satisfied with the depth of my answer, I reshuffle and redo. On the other hand, if the card chosen to be the significator/focus shows up at the end with no cards after it to predict an outcome or to give more insights, I would keep in mind the two or three cards right before it and reshuffle my deck with a strong intention to focus clearly on my question." (350)
Also,
"Follow your gut and do what feels right for you; when in doubt, re-center yourself, focus, and start over so that you can find the flow." (351)