All devices, regardless of the classification, are required by Article 5, 2. to fulfil the general safety and performance requirements of Annex I.
Start with planning the various risk management activities listed in Chapter I. Keep in mind that risk management during development doesn’t finish with a positive benefit-risk report. The final step is the preparation of the post-market surveillance plan (Article 84 and Section 1.1 of Annex III).
Read through Chapter II and make a list of the applicable requirements for your device. Consider how each of those requirements will eventually be shown to have been satisfied during the development. Most companies create a requirements checklist.
Identify any “harmonised” EN and CENELEC standards” (Article 8) which are applicable, and any EU “common specifications" (Article 9) which have to be fulfilled. Lists of these are published in the Official Journal of the EU.
Don't forget that other EU directives and regulations may also apply to the device. For example; environmental (e.g. for batteries) or health & safety (e.g. for hazardous substances) regulations.
Finally, consider also how you are going to satisfy the various “information” requirements (i.e. labelling and instructions) listed in Chapter III.
Deliverables for demonstrating compliance:
(1) The Risk Management file,
(2) The General Requirements checklist,
(3) The labelling and instructions for use,
(4) The Post-Market Surveillance plan.