Obviously practicing is the number one key to getting good and staying good. But I also highly recommend a few other things to advance more quickly in drumming.
Listen to a lot of music, different styles, genres, and artists, and learn to "speak" the different stylistic languages very proficiently. Jazz, blues, and pop/rock all have very different stylistic conventions, but learning those conventions makes you a better listener and player. You begin to be able to anticipate directions in music, play for the song, and catch little nuances that bridge the gap between functional player and musical player.
If possible, attempt to pick up a second instrument. Keyboard instruments, guitars, and basses are popular choices for drummers. You already play guitar, so think about drumming in terms of what you as a guitarist would want the drummer to do. You already learned a big lesson - solos are just that, not multi-instrument freakout moments. But from there you can also understand the musical nuances of songs from another perspective. If the guitarist does a lick at the end of the vocal line, do the drums follow the lick, accent the lick, or keep steady? These are all valid choices depending on the style, the dynamic, and the song.
Study the instrument and how to wring tone out of it. I am constantly amazed at how guitar players will obsess over strings, pedals, amps, effects, even the brand of cord they use to get a certain sound or tone. But the majority of drummers are in the dark about how to even tune properly, much less how to play the instrument musically versus beating the crap out of it. At some point the sound has to evolved from thud-bang to something sonically pleasing. The answer is usually not in gear selection, but in a bit of knowledge of the instrument's mechanics and a lot of knowledge of how to use touch and feel correctly.
And play out! Play with folks at all skill levels. Challenge yourself in playing situations. We learn best by doing.