You need a 30mm socket. They're not exactly bolts at the top, but you do have them. They are nuts that retain the valve cover by threading onto the spark plug tubes, so with the four cylinder engine, there are four. Would recommend checking the Haynes manual. There are locations that require "FIPG" (form in place gasket material) when replacing the valve cover gasket. A spot of sealant goes where the round portion of the cams meets the flat portions of the gasket sealing surfaces. You don't have to use Toyota brand FIPG (I did), but you do have to use a type of RTV sealant that avoids acetic acid in the compound to avoid damage to your oxygen sensor, and the Toyota brand FIPG works very well. Also, be sure the sealing surfaces are completely clean and free of any oil. Good idea to use a solvent first, before placing the gasket. Berryman B12 carburetor cleaner is good because it dries without a residue. You might want to think about replacing the PCV valve and grommet while you're there. They're inexpensive and if the valve cover gasket is seeping, the PCV grommet is probably hardened also. If it starts to break in pieces when removing, it is much easier to remove those piece by holding the valve cover upside down. Another nearby seal, that you might want to replace is the distributor seal - inexpensive and not difficult, though you need to check ignition timing when done. Post again for more information if needed. Final caution on the valve cover gasket - the Haynes maintenance and repair manual, with nice photos, lists the wrong torque value for those valve cover gasket nuts at the spark plug tubes. The Toyota Factory Service Manual shows 29 ft. lbs. for the lower threads that install into the head. For the upper portion that you'll be using for gasket replacement, the correct value is 17 ft. lbs. not 29.