Servicing and tune up procedures are in the handbook or manual. However check and gap or replace spark plugs, check and adjust valve clearances, check and clean or replace A/C element, replace fuel filter if needed, check fuel hoses for softening ,hardening or cracks and replace if needed using the correct specification hoses, check and or adjust TPS, balance throttle bodies, check and adjust mixture. Add a cleaner if injectors haven't been serviced or get them serviced. Once all this has been done you have a solid starting point to just follow the servicing/tune up intervals and procedures in the manual.
Regards Martin.
