I have yet to meet parents who have had any luck getting their twins on a schedule much before six months. Accept that a schedule will probably not happen for at least this long (this will depend on babies' birth weights) - and stop pulling your hair out over it. A schedule just seems to happen, and when it does, it will be obvious. Your twins will begin to do things, such as become tired and hungry at very predictable times of the day on a regular basis. A "schedule" means that you will be reacting to what your twins are doing - they will NOT be reacting to what you are doing. My advice? Don't waste your time trying to get a schedule to work - this "miracle" will not happen until your babies are ready.
I remember feeling SO sorry for myself as I waited for this to happen when my triplets were babies. I was exhausted and downright miserable until I decided changed my attitude about it. At the time, I discovered there was a woman in Iowa who had given birth to septuplets (the McCaugheys). Just knowing this really helped me - all I had to do was praise the Lord I didn't have septuplets! Changing my perspective and reminding myself that the situation was temporary did wonders for my outlook and mental health.
For the time being, you can print a free page (and instructions) of our Double Twin Twins Schedule books you don't lose your sanity before any miracles happen! This will also be helpful for visits to the pediatrician, caregivers, getting an idea of how much they are eating, etc. Make copies of several pages, or, you can purchase our pre-printed version here: https://www.justmultiples.com/books/double-time-twins-schedule-book
Print, feed, and stop driving yourself crazy!