I need help cultivating Śīla

I've been seriously practicing since last August at this point & my meditation is going very well, but my ethical conduct is an obstacle for me right now. I think that my mind is still too closed off & self-absorbed, lacking the openness & spaciousness that comes from selfless action. I'm not a mean person & I don't consider myself to be especially greedy but I also am not actively working to help others, my focus at this point in my life is on helping myself. The 4th precept is a problem for me, I do make white lies or hide the truth out of convenience at times. When it comes to dealing with this, how do I cultivate the mindfulness to combat it? It's such an ingrained habit at this point that I rarely notice it, I'm simply aware that I do it. The other precepts are not a problem for me. But what can I do beyond the precepts? What's a good way to practice Dāna as a 19y/o college student? How can I approach this in a way that's natural & relaxed as opposed to a struggle that will cause me stress?