Keeping pasta warm for a long time is a challenge for even the most experienced cooks and caterers. Pasta can turn too soggy and soft when kept in liquid, but without it, pasta becomes chewy and dry. A slow cooker, along with a small amount of oil and liquid (preferably sauce, but water will do), can keep pasta warm and moist without overcooking.
Cook pasta according to the instructions on the package. Once it's al dente (fully cooked but not overly softened), remove it from the heat and strain it.
Place the pasta in the slow cooker with olive oil and water or sauce. Toss thoroughly to coat.
Set the slow cooker on low heat.
Replenish the water or sauce every 30 minutes.
Every hour, check for texture and replace with freshly cooked pasta as needed.