You can make a surface cooler by roughening it to create more texture. The idea is that a textured surface feels cooler to a bare foot than a very smooth texture, even though both are exactly the same temperature. This is because a bare foot is contacting more surface on the smooth finish than on the textured surface. This is the principle behind many of the deck coatings sold to make a deck cooler.
Therefore, an option is to roughen the surface to whatever degree is still an acceptable appearance to you. Generally, this will involve renting some sort of sanding or grinding machine from a rental yard. This surface will also be made more absorbent and subject to staining with this process. Then, protect the surface with the sealer.
Note 1: You will not want to create much gloss with the sealer or you are defeating the purpose.
Note 2: If the surface is hot because it was sealed and that sealer has made the surface too smooth, see Problem Solving for "Redoing a Previously Sealed Surface". The old sealer can be removed and then seal it again with the appropriate Aldon sealer that will give you little or no gloss.