Here's another tip for any instrument. Concentrate on making every note sound as it should - and play at a speed which is appropriate to do so. In other words, start slowly and only build up to the requisite tempo when every note still sounds perfectly. If you fluff a note at higher speed - reign in the speed.

Use a metronome of equivalent to regulate your speed. Set the temp slow at first and then increase as necessary. After 50+ years of playing, I can still feel myself speeding now and then - carried away by the energy of the moment(!) - and I often record using a Garageband bass track to keep myself reg'lar.