Buying: Unless you have bought pre-softened/pre-shrunk fabric, count on 1/8 yard worth of shrinkage.
Pre-washing: If you want your linen to soften up, prewash it, multiple times even. If you want to maintain the crisp texture (good luck there!), you will have to dry clean.
Pressing: Press the fabric when damp on high heat, use a press cloth to prevent scorching. Press on the wrong side of the fabric to hide the shine that pressing tends to leave on linen.
Needles: Universal needles are fine for most weights, 8-12 stitches per inch.
Other Considerations: Linen ravels easily, so finish those seams.
As you can see from Yorktown Road‘s work, linen takes manipulation techniques (folding, pleating, pintucks, etc.) beautifully. Spray a 50/50 vinegar/water solution to dampen the fold line, then press with your iron.
Sources for this post, and more information:
Flickr Group: Sewing With Linen Lots of inspiration here.
Denver Fabrics: Sewing guidelines
Threads Magazine: Comprehensive article about linen, including interfacings and more advanced garment sewing techniques
Fabrics-store.com Blog: post about general sewing techniques with linen
I know that Japanese craft magazines are also wonderful sources for linen projects and inspiration — can anyone point me to specific titles?