This question is all sorts of vague, but I'll try my best.
My suggestion is GHRP-6. Reconstitute with BA water. GHRP-6 is a GH secretagogue that is known to boost appetite but help maintain leanness by boosting growth hormone levels and also helps give more quality sleep when taken at night before bed (by matching the nocturnal GH surge).
The appetite increase might be a problem so the more expensive GHRP-2 can be used, though it is known that the body can build up a slight tolerance to GHRP-2 as opposed to GHRP-6. Hexarelin is also an option, though the tolerance can be much higher. The appetite increase is hardly a problem with Hexarelin.