...what's really worked for me is going through old and new testament both at once...
There's a way of reading the Bible that I've found to be a great blessing. You can think of your Bible as 6 volumes: 1. Romans to Revelation, 2. Matthew to Acts, 3. Isaiah to Malachi, 4. Job to Song of Solomon, 5. Judges to Esther, and 6. Genesis to Deuteronomy.
You can read one chapter in each volume every day, for a total of 6 chapters a day. Continue to read one chapter in each volume every day even after you've completed the smaller volumes. When you reach the end of a volume, simply begin again at the first chapter of that volume. In this way, you will be going through the smaller volumes more frequently than the larger ones, but that's okay because the smaller volumes happen to be the most important.
The 6-volume method will keep you current in every part of the Word; there won't be any book that you haven't read in years. Also, it's amazing the connections you will see between the volumes when you are in them all at the same time. Lastly, you will find it easier to read more of the Bible each day, and to continue reading it day after day. I have heard people say things like: "I started in Genesis but couldn't make it through Leviticus. I haven't picked up the Bible since."
This method will have you going back to the buffet of the Word every day. But like a buffet, don't try to eat too much in one sitting. You will be tempted to increase the portions from one chapter in every volume every day to two chapters and then three. You can "burn out" on the Word just like you can on eating too much meat. Eat a daily portion that will keep you hungry enough to come back every day. A moderate portion every day is better than a huge amount for a few days and then nothing for a year or two.
When we don't read the Word for a few days, I believe it can have the same effect on our spirits that not eating for a few days can have on our bodies. We can get tired spiritually, and hungry for the wrong things. So we should consider reading the Word to be as important as eating, for "Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God" (Matthew 4:4). Indeed, we should consider reading the Word to be even more important than eating, for "I have esteemed the words of his mouth more than my necessary food" (Job 23:12).