For standard oil paints, the best way to ensure faster drying is to mix a touch of thinner (preferably mineral spirit which is similar to turpentine) and also painting in very thin layers. This would be a preferred way, for example, to do the very first underpainting layer. Also allow the painting to sit in a decently-lit space with good ventilation but don't put it in direct sublight as it may cause the oil in the paint to dry too quickly and crack the texture. Adding Liquin Impasto can also help with drying time without thinning the paint out very much, depending primarily on how much you add to the paint. Adding oil-based mediums adds to drying time so try to limit your use of such mediums if drying time is more important to you.
Normal oil paint drys within 3-12 days depending on the particular color, brand and thickness as well as how much and what type of medium is mixed with it. For the absolute fastest-drying oil paint, you can choose to use alkyd-based oils which dry very quickly (within 18-24 hours, with re-workability limited to the first 8 hours). To hasten the drying time even more, use Liquin Impasto as a medium to mix with alkyd-based oils. It's not uncommon to achieve dry-to-touch results with that kind of mixture within 12 hours so long as other conditions are optimal (sparing use of mineral spirits, minimal to no use of oil-based mixing mediums, a space with good ventilation and indirect sunlight).
