Apply for leaves at work and ask the rest of your family members to do the same a few weeks before the actual trip.
Convince everyone in the family to join this vacation and inform them about the plan beforehand so they can manage their schedules accordingly.
Sit together and choose the place where you all want to go. For your vacation it is always a good idea to pick a tourist resort. Browse the websites of different tourist havens to make a decision regarding the place you want to take your family to.
If you need to fly or catch a train, book the seats well before the departure date. Remember it is very difficult to get tickets during holiday seasons, so plan ahead.
Decide which airline or train service your family will be comfortable with. If there are any recommendations, consider them, or put the means of travel up for a vote.
If you are travelling with kids, make sure that the destination is children friendly, meaning that the place needs to have some interesting sights for kids and should be generally safe for them to play freely.
You will need to do some research in order to find a good hotel for your family to stay in. Check the websites of these hotels and see which services they offer and what they charge. You can also decide on rooms and floors and consider facilities like an in-house restaurant etc.
Always carry a first aid kit while travelling and ask your family members if they need any special medication to be packed. If someone is prone to allergies for instance, make sure you have the requisite medicines.
If you have any pets, then arrange a pet sitter well before leaving. You can also leave your pets with a willing friend.