get a good top view and side view of the board.
sketch one quarter of the board from the topview sketch.

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extrude the sketch to the required thickness.

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realign the extruded body. I find it to be easier to center/align the extrusion then to do it with the sketch/canvas. this is just my way of doing things.

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mirror on x/y axies.

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this body is just for the purpose of getting the basic shape of the board and for getting it perfectly aligned.
create form is what I used to get the concave for the deck.
make sure you have several images of the board from multiple sides so you can get a better idea of what the concave of the deck should be like. I own this deck so I had it in front of me to measure and I was constantly rotating it around in my hands to get the shape right. the create form tool is kinda difficult to use I’d recommend watching a video on youtube. it really helps.

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thicken it then cut it using the face of the flat body from earlier. I use intersect for this.

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