Hi,
This is just common sense approach: not expert opinion!
1st, if baby breast feed, ensure u burp well & can hear the sound of eructation of swallowed air. Burping has to be done when baby awake (or else wake baby up), & also offer areola plus nipple while feeding (not areola alone)
If bottle fed, use peristaltic nipple, as it has special mechanism to prevent air being swallowed along with milk & keep bottle upright so that air doesn't fill the nipple!
Using anti-frothing agents/Simethicone will help.
Also, for 45minutes after feed, keep baby tilted to right lateral side, under supervision.
Next Steps
If poor response, always review personally with mother's gynecologist or baby pediatrician at earliest, as crying spells can become a habit
Health Tips
There is a known issue called "evening colic": please look up same!