How deal with liberal color revolution?

Prevent it through prohibition of private media, and don't turn the economy of your country into a treat competition between you and the US

Keep NGO's on a short leash. Shut down any media, organisation or party related to the US security state, or at least innoculate the population against them by demanding full transparency about their funding and pointing out who pays them. Mobilize the masses to show support (has worked in Cuba). Treat members of your security forces well and weed out reactionary elements.

Most important: Do not be an incompetent and corrupt prick that people are genuinely fed up with. Do good governance, even though times are tough due to US economic warfare. Be as honest and transparent as possible about the priorities you make and the scope of the problems you face and be in constant connection to the masses so you know what problems they face and how your decisions impact them.

Serve the people faithfully to prevent it, and enlist the ones you trust in Committees for the Defense of the Revolution to combat it.

They draw in the petite bourgeoisie. Deal with their class interests.

though seriously, you need to hit the funding sources. In this century, it's all about the Benjamins. American soft power ain't what it used to be with their old VoA crap. These color revolutions now get organized off of people being paid extremely lucratively in USD compared to your weak local currency. You can't allow people's full time job to be overthrowing you. Bust up their NGOs and drown them in lawfare. There's a reason all these post-Soviet States are throwing temper tantrums over "Putinist foreign agent laws": they work. In a capitalist economy the people are always going to feel aggrieved and American agents will exploit that and twist it to liberal ends, "anti corruption" movements are the classic slogan. What they don't tell you is that the plan is to just privatize and outsource the corruption, not eradicate it.

Furthermore, give yourself output legitimacy by increasing the standard of living among the population however you can, that's part of the deal of being long time government leader. Conveniently, socialist policies are a sustainable way to accomplish that, though you will have to subdue your domestic bourgeoisie first which is easier said than done under imperialist pressure. Cutting a deal with them may be easier but dangerous long term.

just don't borrow from the IMF. You and your minions can be corrupt but not lavishly so