Start before you even fall pregnant (if possible!)
Get yourself and your partner in good shape, adjust your diets, get fit. If you’ve been on birth control it’s always a good idea to see your health care provider.
Discuss your thoughts and fears with your partner – thing like number of children you want, how you want them spaced, your thoughts on discipline, how were YOU raised?, thoughts on raising children, what is negotiable and what will you not budge on, birth options, working mum or stay-at-home parent (mom or dad)?, childcare options? Remember that EVERYTHING you decided on can and probably will change in some way or another and you have every right to change your mind and re-evaluate how you want to do things but bear in mind that your partner can have the same change of heart. Starting now to discuss things and approach as a united front is good practise for later on.
Relax and enjoy yourselves! Making a baby should be a joyous event.