I agree with Christy and JTReed, no mealworms......I don't even give my adults them.....they are not very strong nutrionally and the exoskeleton in small ones can be deadly. When my dragons reach 12 inches, I then use superworms as treats, they don't have the exoskeleton and have better food value as they are meatier.
I would ditch the potting soil.....it often has additives which can be harmful if ingested and hatchlings aren't the best at catching their food and often get a mouth full of substrate with or without the cricket they are chasing. Although many experienced keepers use playsand from the start, they also know what to watch for as symtoms of impaction which can occur with sand......as a new keeper, I highly recommend you use paper towels, butcher paper or newspaper until your dragon is at least over 8 inches, preferalby 10....then you can switch to playsand or wheat bran like I use now.
You may have to order your crickets online to get the correct size ones and he really needs the crickets, or you could order small silkworms or eggs to grow silkworms. Pet stores often have only small or large and the many of the smalls may be too big. Check around for a local reptile shop....they often sell smaller crickets.
I would also ditch the cactus as JTReed said......a beardie with cactus tines stuck in him would be one unhappy beardie.....