Before preparing preventive maintenance for your equipment, forget it is an equipment, think about it as a living creature, best to consider it your child, then ask yourself, how can I keep my child healthy all the time, think what are different diseases he can catch, and put a plan to vaccinate him, and measuring points that will tell you how is he performing, then in case he got ill, how you can treat him to return to his shape! All these together will create the preventive plan.
The best approach if accurate information and technical knowledge is readily available and time allows is to build your PM plan based upon the actual failure modes experienced or likely to experience. This means performing an FMEA. Mark suggested purchasing a template of ready made PM's if the equipment is within the data base. I like this approach, however running it through a validation filter with members of your team is an important step. You are likely to find and make subtle changes, but the biggest benefit is the ownership of the asset care plan by the team when they have an opportunity to invest time and energy into making it fit their equipment.
The best source document is the OEM and the maintenance interval list gives the frame work for your preventive maintenance plan. It is important to understand that this is a dynamic process and requires constant review and revisions as we gain more insight into the equipment performance through its life span.
If the equipment has been in place for a while then existing work history needs to be brought in as part of the data for decision making. In one plant we made a three person PM development team that built the PM program from work history. We brought together the most knowledgeable mechanical maintenance tech, electrical / controls tech and operator for a few months. Their assignment was as dedicated caregivers to the paper machine. For 3/4 of their work day they performed field work such as the OEM recommended inspections, additional inspections based upon similar equipment, checks that they thought of based upon their personal experience, and minor corrective repairs on the machine. The final 1/4 of the day we had them document the details of the work that they performed. They were also validating and enhancing the activities they were performing. Out of this effort we had a very comprehensive PM program and the team had a very high level of ownership in seeing the PM's were performed and followed up on.
The OEM Manuals can be a good starting point if you do not have anything else, however they should not be left as the default PM program. If you settle here you will not have the robust PM process that you desire. Optimizing of OEM Manuals is not a priority with most equipment suppliers. I can think of many reasons why this may be, but the bottom line is no one will be as in tune with how the equipment may fail and therefore the warning signs of progressing failure than end users. Coordinate with other users of the same equipment and mine the data from your own experience with the equipment.