I have been venturing out on the water, including offshore most of my life in craft from 12' to 60'. There is no substitute for making sensible cautious decisions based on knowledge and experience. I strongly recommend learning about the basics of weather and oceanography and talking to people who know the quirks and peculiarities of the areas you plan to go to regularly.
This isn't as onerous as it sounds. Look at charts to see where the sea floor is higher or lower. Look at weather charts and forecasts to gain an understanding of how certain conditions will affect the places you want to go. Find out about local weather patterns... are there any localized events that can occur under certain conditions that may catch you by surprise if unprepared.
Don't be scared to get experience. Pick some days that are outside your current experience and comfort zone, not too far beyond but enough for you to learn how your boat handles and to see and experience different conditions. Leave the family at home, nothing freaks them out more than the skipper being nervous and unsure, take someone you trust and preferably with experience but without bravado.
The law here (and common sense) says Type 1 PFDs must be carried offshore, along with VHF radio, flares and an EPIRB if more than 2nm out. Also make sure you have freshwater in bottles that be taken with you if you have to abandon ship. I cannot stress how important an EPIRB is. If you ever wind up in dire straights then this will get you help fast. The newest ones receive and broadcast GPS to the COSPAS/SARSAT system for a precise fix for rescuers to focus on.
You will be surprised how quickly you will learn and feel more comfortable with venturing offshore. When checking forecasts and making the 'go or no-go' decision my golden rule is 'if in doubt, don't go'. There have been plenty of days I have err'd on the side of caution and missed a great day. But that's tempered by days of going to the aid of others who went 'outside' and got beaten up by changing conditions that left them too sick to function or the boat damaged.
Most of all have fun while learning.